Category Archives: Fall gardening

No More Buds? Turn to Earbuds.

By this time in the year, I’m at the point of good riddance! with the weeds and careful tending (shout out to this cold spell for sealing the deal). Pretty much everything is done and put to bed. I then spend the next two weeks really dialing into my houseplant game before I get bored and start Spring dreaming. My Fall break from the garden is short-lived so I start listening to old episodes of now-defunct podcast series and dream with new ones.  Here are a few of my favs:

Gardenerd Tip of The Week

Gardenerd.com is the ultimate resource for garden nerds. We provide organic gardening information whenever you need it, helping you turn land, public space, and containers into a more satisfying and productive garden that is capable of producing better-tasting and healthier food.

https://gardenerd.com/

My thoughts: The host lives in LA, so this one is great for winter listening as we get chillier, I love hearing about the warmth of Southern California and what’s coming into season. Interviews with other experts and educators in the horticulture field discussing plants, but also cultivating grains, discussing bees, and seeds. Each episode ends with the guest’s own tips, many of which are news to me and have been incorporated into my own practices. 

On the Ledge

I’m Jane Perrone, and I’ve been growing houseplants since I was a child, caring for cacti in my bedroom and growing a grapefruit from seed; filling a fishtank full of fittonias and bringing African violets back from the dead.

https://www.janeperrone.com/on-the-ledge

Houseplants, if new to the podcast start here for an overview, and guidance.

Jane is a freelance journalist and presenter on gardening topics. Her podcast has a ton of tips for beginners, and more advanced info for longtime houseplant lovers, as well as interviews with other plant experts. The website is also useful to explore the content of an episode if you aren’t able to listen. I could spend an entire morning traveling in and out of the archives. 

My thoughts: As the growing season comes to a close, my indoors watering schedule starts wobbling between what the plants need and my summer habits of watering too many times per week–welcome back,  fungus gnats! Here’s an entire episode on them

Plant Daddy Podcast

We aim to create a listener community around houseplants, to learn things, teach things, share conversations with experts, professionals in the horticulture industry, and amateur hobbyists like ourselves. We also want to bring the conversation beyond plants, since anybody with leaf babies has a multitude of intersectional identities. We, ourselves, are a couple gay guys living in Seattle, Washington, with a passion for gardening and houseplants. A lot of our friends are the same, though each of us has a different connection, interest, and set of skills in this hobby, demonstrating a small amount of the diversity we want to highlight among plant enthusiasts.

https://plantdaddypodcast.com/

My thoughts: Plants are visual, podcasts are auditory- episodic overviews with links to viewable content available on their website. Are you also seeing Staghorn Ferns everywhere? They have an entire episode (photos included!) on the fern and how to properly mount it for that vegan taxiderm look. Matthew and Stephen are self-identified hobbyists with a passion for plants all the way down to the Latin–it’s impressive.

Epic Gardening

The Epic Gardening podcast…where your gardening questions are answered daily! The goal of this podcast is to give you a little boost of gardening wisdom in under 10 minutes a day. I cover a wide range of topics, from pest prevention, to hydroponics, to plant care guides…as long as it has something to do with gardening, I’ll talk about it on the show!

https://www.epicgardening.com/

My thoughts: The Netflix-episode-when-you-just-don’t-feel-like-a-movie kind of podcast. Addresses the best varietals, composting, soil pH, and troubleshooting some common issues in the garden. With daily episodes archived back to December 2018, there is a quickly digested thought for some of your own curiosities. The website is also a wealth of knowledge. 

Eatweeds Podcast: For People Who Love Plants

Eatweeds: An audio journey through the wonderful wild world of plants. Episodes cover modern and ancient ways wild plants have been used in human culture as food, medicine and utilitarian uses.

http://eatweeds.libsyn.com/

My thoughts: most recent episode (and appropriately timed!)  On edible acorns. My fav topics include foraging and wild yeast fermentation; and when I really start missing the Pacific Northwest, The Wild and Wonderful World of Fungi sends me back to a misty forest wander politely decorated by les champignons. Posting of this pod is sporadic–only 25 episodes since 2014.

You Bet Your Garden

(no longer on air, but archives available)

 

You Bet Your Garden® was a weekly radio show and podcast produced at WHYY through September, 2018. The show’s archive is available online. It was a weekly syndicated radio show, with lots of call-ins. This weekly call-in program offers ‘fiercely organic’ advice to gardeners far and wide.

https://www.wlvt.org/television/you-bet-your-garden/

My thoughts: Host, Mike McGrath, spends much of the show taking calls and troubleshooting, reminiscent of another public radio behemoth with Click and Clack, the Tappet brothers. McGrath incorporates a lifetime of organic gardening tips with humor. McGrath features one tip to find a local “rent a goat place” (no joke) to get goats to eat the most troublesome weeds to a concerned caller considering setting much of her yard on fire.

Cultivating Place: Conversations on Natural History and the Human Impulse to Garden

Jennifer Jewell, the founder of Jewellgarden and Cultivating Place, achieves this mission through her writing, photographs, exhibits about and advocacy for gardens & natural history and through her weekly public radio program and podcast Cultivating Place: Conversations on Natural History and the Human Impulse to Garden, on gardens as integral to our natural and cultural literacy.

https://www.cultivatingplace.com/

My thoughts: sort of like On Being, but for gardening.

A fav episode:

If you aren’t so sure about this podcast thing, and just want a place to start, start here.

Do you really need a brain to sense the world around you? To remember? Or even learn? Well, it depends on who you ask. Jad and Robert, they are split on this one. Today, Robert drags Jad along on a parade for the surprising feats of brainless plants. Along with a home-inspection duo, a science writer, and some enterprising scientists at Princeton University, we dig into the work of evolutionary ecologist Monica Gagliano, who turns our brain-centered worldview on its head through a series of clever experiments that show plants doing things we never would’ve imagined. Can Robert get Jad to join the march?

https://www.wnycstudios.org/podcasts/radiolab/articles/smarty-plants

The Weather Outside is About to Change

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October is the month the garden takes its final breath, the first frost arrives (this week!) and pumpkin-everything surrounds us. We’ll still have some beautiful fall days, but there’s no denying it, the growing season is coming to a close. So with that in mind, here’s a round up of helpful information for the days, weeks and months ahead.

  • Sometimes working less is working smarter – find tips for putting the garden to bed here and here.
  • Why am I always late scheduling this? Instructions for winterizing sprinkler systems here. (It’s helpful to read even if you leave this task to others.)
  • Have your houseplants been living outdoors? With temperatures about to plunge, it’s time that vacation comes to an end. Some good reminders on how to help them transition to lower light can be found here. 
  • My Chanticleer Pear tree (Pyrus calleryana ) is soooo prone to storm damage in both the fall and the spring – this CSU PlantTalk article provides excellent information on snow-load damage and pruning of herbaceous plants.
  • If you have upright junipers, you know they are also prone to winter splitting. Here are some excellent tips on preventing structural damage, including a creative use for Christmas lights.
  • And finally, be mindful of the winter moisture levels. “Your Yard is Thirsty” offers advice on winter watering of a variety of plants.

Written by Linda McDonnell, a Denver County Master Gardener

Image by Anne Hughes, a Denver County Master Gardener

 

 

Transplanting Peonies

Image: Pixabay.com

Many gardeners eagerly await the annual early summer explosion of peonies. Whether ruffled, double blossoms or open-faced single flowers, peonies make a striking display, particularly in established cottage-y perennial gardens.

Adding to their popularity, they are relatively disease-free and long-lived. Unlike many herbaceous perennials, they do not need to be divided every few years. In fact, they prefer not to be disturbed. However, transplanting is a smart choice if the location has become too shady, the plant has outgrown the space or aesthetically it just isn’t in the right spot.

Fall is the very best time to move the plants as they are not actively growing and are preparing to go into dormancy. If transplanted in September or October the roots will have time to settle in while temperatures are cooler but before frost sets in.

Here are some tips for successful transplanting this popular plant.  

Removal –  excavate as much root as possible, by digging straight down and around the plant about eighteen inches from the crown. Carefully lift the root ball from the soil and try to avoid breaking the stems. The foliage can be trimmed at this time; it will yellow and die after the first frost.

Relocation – choose a site that gets at least six hours of full sun to insure prolific blooms.  An added benefit of fall transplanting is the ability to properly space the plant in the full grown garden. Edit surrounding plants if needed to accommodate the new resident and allow for good air circulation.

Preparation – the planting hole should as large or slightly larger than the rootball. Amend the hole with one third to one half of compost mixed into the garden soil to improve drainage. Peonies will not thrive in heavy clay soil so don’t skip this step if your soil drains slowly.

Peony “eyes” and root stock. Image: University of Pennsylvania Extension.

Planting Depth – the “eyes” of the plant should be planted no more than two inches deep. This insures the plant will bloom successfully. The “eyes” are the white or pink fleshy nubs on the rootstock; they will become next year’s flower stems. Peonies that produce few blooms are often planted too deeply.

Division – if you choose to divide the plant, each new segment should have at least three to five eye buds and attached roots. Divisions can be cut with a knife and inspected. Discard if the clumps show signs of insect damage or are mushy. 

Moisture – water well once transplanted and watch for periods of prolonged drought through the winter. Plants can be mulched after frost sets in. 

The plant may take an additional year to get comfortable in its new home and rebloom. Don’t despair – given a sunny location, proper soil preparation and planting depth, your peony will thrive for many years to come. 

Additional Resource:

https://planttalk.colostate.edu/topics/annuals-perennials/1042-peony/

Written by Linda McDonnell, Denver County Master Gardener


Your Yard is Thirsty

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When I moved to Colorado three decades ago I expected to be knee-deep in snow and cold to the bone for months on end. Little did I know, Denver winters have long dry stretches, moderate daytime temperatures and bright sunshine that melts snow before it needs to be shoveled. So much easier than the New Jersey winters of my youth. The downside is that plants often suffer from lack of moisture. This year I’m being especially diligent about winter watering to help  newly planted trees, shrubs and perennials make it through their first winter and thrive in the future. Whether nurturing young plants or insuring the longevity of established ones, here are Colorado State University’s recommendations for cold season landscape care.

  • From November to March, give plants a good drink when four weeks elapse without snow cover or adequate moisture. March is the metro area’s snowiest month (11″); January (7″) and February (6″) average the least.
  • Water when temperatures are above 40° and early enough in the day for the moisture to soak into the ground before temperatures dip below freezing.
  • Reflective heat from buildings, the lower angle of the sun and areas prone to intense wind cause root systems to dry out more quickly, watch plants in these areas closely and water accordingly.
  • Newly planted trees establish slowly – one year for every inch of trunk diameter, (measure 6″ above the soil ). A good rule of thumb is to apply 10 gallons of water per inch of trunk diameter each time you water. Water around the tree, out to the drip line and beyond. The goal is to send moisture to the tree’s entire root system at a depth of 12″. I’ve found running a sprinkler for 30 minutes does the job nicely.
  • Newly planted shrubs require more moisture than established ones (over one year old). A first year, 3′ tall shrub requires 5 gallons per watering.
  • Mulch is a plant’s friend – it helps maintain moisture and mitigate the damaging thaw/frost cycle.
  • Newly seeded lawns and perennials (especially fall planted ones) will benefit from supplemental watering if precipitation is low, too.

According to globalwarmingdenver.com, we’ve received just .02″ moisture in the last two weeks and are about 2.5″ below average precipitation year-to-date. Given our dry days and spring-like temperatures, it’s  about time to unwind the hoses.
For more information:
Planttalk Colorado: Fall & Winter Watering
Colorado State University: Fall & Winter Watering Fact Sheet 7.211

Photo credit: Pixabay.com, a source for royalty free images
Written by: Linda McDonnell, a Denver County Master Gardener

Fall in the Perennial Garden

 

McDonnell summer border 

I don’t know about you, but in my  garden, fall cleanup can be hit or miss. Whether a function of limited time, gardener burnout or an early cold spell, some years I just let it all freeze dry in place till the spring. I’ve learned to embrace the  appearance and find that doing less offers the garden many benefits, including:

  • Dried foliage will help protect the crown of perennials from the freeze/thaw cycle; this is especially good for marginally hardy perennials. If  you do prune, leave about 3-4 inches from the ground to avoid damaging the crown.
  • Dead stems “mark” the plant and lessen the chance of accidentally digging it up or stomping on it in the spring. This is really helpful for plants that “wake up” a bit late in the spring.
  • Leaves will decompose and add organic matter to the soil. They can also insulate plants from harsh winter temperatures.
  • Dropped seeds produce new plants to fill out your garden or share with others.
  • Seed heads provide tasty food for birds.
  • Some plants prefer spring pruning, such as grasses and plants with semi-woody stems like Munstead Lavender and  Wild Thing Sage or Salvia Greggii. A spring haircut when new growth emerges often yields a plant with better form and growth. (Not to mention increased chance of winter survival.)
  • Early season flowering shrubs such as lilacs have already put on the

    Photo from CSU CO Master Gardener Garden Notes

    growth that produce next year’s flowers. If you cut now, you will not have blooms next spring. These plants should be pruned shortly after blooming, or  you may have a lilac that looks like this!

Fall garden clean up does not need to be back-breaking work. Just remove diseased or mildewed foliage, lightly cut back long limbs that can be  damaged by strong winds and occasionally water if conditions are dry. Your garden will benefit from this “less is more approach”.

References:

Winterizing Perennials, Plant Talk 1020

Maintaining Perennials, Plant Talk 1019

Winterizing Perennials During Drought, Plant Talk 1064

Written by Linda McDonnell, Denver County Master Gardener. 

A version of this post was originally published in October 2015.

 

Never Put a $10 Plant in a 10¢ Hole and Other Gardening Tips From Denver Master Gardeners

planting-1898946_1920Passionate gardeners love to talk about gardening, so with that in mind, we recently asked Denver Master Gardeners for their best gardening advice. Responses included tried-and-true practices, creative suggestions and good reminders for all of us as the gardening season kicks into full gear.

As the title of this post implies, we believe that great plants come from appropriate soil preparation. Amending with compost is often imperative as soil in our region tends to lack organic matter. But proceed with caution, as some plants, such as natives, prefer a leaner, less fertile soil. Too rich soil will cause these plants to underperform and often just flop over. It pays to do a little homework before planting, read seed package directions and have your soil tested.

One of our gardeners shared her recipe for amending soil: Add 1/2 a handful of both Alaskan fish pellets and triple super phosphate to half a bucket (such as a kitty litter pail) full of compost. Mix this into the planting hole for strong root development and beautiful blossoms.

A tip borrowed from the Rock Garden Society is to plant bare root. By gently shaking off most or all of the soil that the plant is purchased in, the plant will adjust to the garden soil without the soil interface (or boundary) that can occur between two soil types. Bare root planting promotes healthy root development.

mulch-1100555_1920Mulch, mulch, mulch is the mantra of many of our survey respondents as it keeps weeds out and moisture in. Add it like crazy each time you dig in the veggie, perennial and annual gardens and don’t forget container plants too. Small to medium-sized bark chips are popular, practical and pleasing to the eye. Natural mulch options are very effective, including not quite finished compost from the compost bin which will add carbon, feed living organisms, prevent water runoff and prevent compaction. Local arborists are often willing to drop off wood chips which would otherwise fill up the landfill. In the fall, mow over your leaves and spread them throughout the yard, they’ll breakdown by spring and add organic matter to your soil. Consider purchasing a chipper to grind up branches and other garden waste.

garden-hose-413684_1920Suggestions for responsible use of water include watering when the plant needs it instead of on a set schedule. Soaker hoses, often made from recycled material, are effective for watering plants at the soil line. Plants (even xeric ones)  need moisture to maintain healthy roots and overall strength, but often less than we think. For example, the Water Smart Garden at the Denver Botanic Gardens is watered about seven times during the season.

Weeding can feel like a no-win battle, but attacking weeds after a soaking rain makes the task easier. Pull weeds and unwanted volunteer shrub and tree seedlings when they are small, before they take hold in the ground or develop seed. Add stepping stones to the garden to avoid stomping on plants and compacting soil when working in the garden.

bindweed-1207738_1920A clever tip to eliminate stubborn weeds, such as the nasty bindweed shown here, is to take a large piece of heavy cardboard, make a cut from the edge to the center. Keep the cardboard as level as possible, slip the vine in the center and spray the vine with the herbicide of your choice or horticultural vinegar, which is sold in garden centers. The cardboard will protect surrounding plants from overspray. Aggressive weeds may require multiple treatments during the season.

One of our members recommends a tomato planting technique passed on through generations of farmers. She adds blackened banana peel to the soil and feeds them with skim milk upon planting and again one month after that. This less conventional practice yields her sweet, abundant fruit. While CSU can’t vouch for the scientific efficacy of this, the banana could be adding potassium and the addition of calcium may reduce the chances of blossom end rot.

plant-1585251_1920Growing tomatoes in containers is recommended for those with limited space. Select varieties which produce smaller fruit such as Patio, Cherry or Sungold. Use a large container (18+ inches in diameter), a sturdy support and a tray with casters. This allows plants to be moved from the path of hail or to optimal conditions. Container plants of all kinds benefit from weekly feeding of 1/2 strength fertilizer.

To keep pests at bay, try a thorough weekly spray of water during the growing season, including the walls of the house and fence. It’s a kinder way to shoo pests away.

If your vines need a sturdier trellis consider building one out of remesh, which can be found at hardware stores. It makes a durable, cost-effective support and can easily be cut with bolt cutters. It also can be attached to supports to create a dog run or create plant cages.

botanical-garden-413489_1920In the flower garden, invest in perennials for texture and dimension and add annuals for bold color. “Enjoy the randomness of some plants that choose their own spots to thrive” suggests one gardener. What a positive way to think of the seedlings that sprout up at this time of the year. Remember, too, that perennials may not come into their glory until the second growing season.

Gardening is a four season hobby. Winter watering of trees and shrubs will help keep them healthy and  veggie gardeners can get a jump on the season by using a cold frame or floating row cover to get an early start on lettuce, spinach and other cool season crops. Fall is a fantastic time to fertilize, aerate and over-seed the lawn. It is also an ideal season to divide perennials so that they settle in and are ready to take off in the spring.  Share your divisions with your neighbors, too, or trade for plants you’ve admired (envied?) in their yards. If you need more gardening space, solarizing or sheet composting is an excellent technique to ready a new garden bed and can be started throughout the year.

And lastly, a veteran gardener advises us to “Remember each little garden flower or planting arrangement is a moment in time. It will change. Don’t worry about it or take it too seriously.”

 

Written by Linda McDonnell with thanks to the many Denver Master Gardeners who shared their advice.

All photos courtesy of http://www.pixabay.com, a source of royalty free images.

Fall: The Science of Color and Options for Clean-up

In Colorado and many other states in the US, we enjoy fabulous fall color in our gardens, parks and wilder landscapes.  We notice it most on trees, but many shrubs and other plants change color in the fall too.  Have you ever wondered where all that color comes from?  Why do the leaves drop off the trees?  And what use are all those huge drifts of dead leaves to us?

Color

Most plants have green leaves.  This is because chlorophyll in the leaves absorbs the red and blue parts of the light spectrum but reflects green light-waves so we see “green”.  Chlorophyll is used in photosynthesis.  This is the chemical process by which plants convert light, carbon dioxide and water into oxygen and carbohydrates – i.e. food for the plant. Chlorophyll is an unstable compound and the plant continuously replenishes it throughout summer when good sunlight and high temperatures prevail.

When temperatures cool and nights lengthen, chlorophyll production stops and so does photosynthesis (the plant’s food production system). As the green-reflecting chlorophyll disappears, other colors “appear.”  In fact, these colors were always present in the leaves but now they are no longer masked by the green light-waves reflecting from the chlorophyll.

Carotenoids absorb blue-green and blue light and reflect yellow light waves.  This is perceived by the human eye as yellow or greenish-yellow.  This is why the fall color of birches and aspens is yellow.

Anthocyanins absorb blue-green, blue and green light and reflect red light-waves.  This is perceived by the human eye as red through to purple.  This is why the fall color of red oaks, sumacs and some maples is red.

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Acer tartaricum ‘Hot Wings’ still green

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Acer tartaricum ‘Hot Wings’ turning red

 

 

 

 

 

 

 

The depth and shades of fall color depend not only on the presence (or absence) of these pigments, but also the temperature and sunlight available.  Low temperatures and bright sunlight destroy chlorophyll.  So, falls with dry, sunny days and dry, cool nights tend to produce the best fall color.

In severely dry falls, the lack of moisture available to the plant may mean that leaves simply die without producing their usual fall colors of yellow, red or purple.  The leaves lose so much moisture that the normal chemical processes cannot continue and the leaves dry, turn brown and drop early.

The ‘Fall’

Once the spectacular show of fall color is over, deciduous (i.e. leaf-losing) trees and shrubs drop their leaves.  Cooling temperatures and lengthening nights trigger plants into sealing off the point on their stems where leaves are attached so that no more exchanges of moisture and nutrients between the leaves and the rest of the plants are possible.  This is called the “abscission layer”.  When this layer is complete, the leaves drop (or “fall”).

What use are those dead leaves?

Think about how nature deals with this “problem”.  Leaves fall from trees to the ground of the woodland, forest, mountainside, meadow – wherever they are situated.  Rain, frost, snow, the trampling of animal feet all help to break the leaves down into smaller and smaller pieces.  A huge drift of fallen leaves decreases significantly in size as air spaces between the leaves diminish.  An army of creatures from the soil surface, and from beneath it, break down the leaves further through eating and excreting them (think: earthworms, beetles) or chemically decomposing them (think: fungi, bacteria).   In this way, the dead leaves are decomposed into the tiny elements that create soil.  It’s a mixture of humus and minerals.  The humus is the last vestiges of the leaves that are hard to break down like cellulose and the minerals are the chemical components of the leaf tissue, e.g. nitrogen and carbon.

The humus and minerals help to form new soil structure in which new plants can seed, germinate, develop and continue the cycle.  The new fertile or replenished soil provides the moisture and nutrients that the now-leafless trees will need to survive winter and re-start photosynthesis and growth in spring.

How to deal with those huge piles of leaves

We’ve seen above that the dead leaves have an important part to play in the garden’s eco-system.  So, what can you do?

  • Just let the leaves remain where they drop on garden beds. They provide great mulch to maintain soil temperatures and protect plant roots and will rot down over winter, improving your soil as they go.
  • Leave a thin layer of leaves on lawns. Rake or blow them off (if you must) but a thin layer of leaves (especially if you run over them once or twice with the lawnmower) will break down quickly and help re-vitalize your lawn.
  • Rake or blow leaves off walkways, drives and sidewalks on to adjacent garden beds, so that these hard landscape areas are visible and don’t become slippery. Do not sweep or blow leaves into the street, as they can cause serious blockages in street drainage systems.
  • For a neater look, you can blow the front edge of borders clear, letting the leaves accumulate at the backs of borders and behind and below larger plants.
  • Put layers of leaves in your compost bin (even better if you can run the lawnmower over them first) between your layers of green garden/kitchen waste.
  • Save the leaves in plastic trash sacks (stored in an unobtrusive part of the yard) and let them rot down over winter, to be returned to the garden when they have decomposed. This leaf mold (the lovely dark brown material you get from decomposed leaves) is like “gold-dust” to the soil.
  • Save the leaves in an open cage made of upright posts and chicken wire to decompose – more “gold-dust”. If you have room, let your neighbors drop their leaves in the cage too.
  • BUT if leaves come from a diseased plant e.g. one with powdery mildew, black spot (roses), apple scab, anthracnose, they should be collected up and disposed of as garbage to help prevent re-infection in the next year.

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Leaf cage made from old timber and chicken wire

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Fallen leaves make great mulch (and are warm and cosy for the dog!)

If none of these options work for you, you can dispose of the leaves in degradable paper sacks which are usually available from your local hardware store at this time of year.  The sacks can be collected with your normal weekly trash service.  Some towns and cities will have leaf drop-off points where you can take the bags for the city to collect.  The city will then use the leaves to make leaf mold for local parks or otherwise dispose of them.  If you can’t do these things yourself, look for a local lawn service company that can, or hire a local teenager to help.

But, whatever you do, remember that the leaves really belong on the ground.  That’s nature’s way, after all.

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Acer saccharinum (silver maple) turned yellow

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Quercus rubra (young red oak) turned red

Anne Hughes/Denver County Master Gardener

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sheet composting or … cooking up an experiment in the garden

I’ve always known that the soil in the garden was the key to planting success.  So, when we started our new Denver garden in 2014 we turned in most of the turf and dug, weeded and added leaf mold to the topsoil.  (We had kept all the fall leaves for this purpose.)  Then all the bare soil was covered with a 3-4 inch mulch of wood chips.  Key trees were planted in spring 2014 with more trees, shrubs , ornamental grasses and herbaceous perennials following in 2015.  We watered diligently till the winter and snow came.  We thought we’d made a good start.

In spring 2016 I was delighted to see our young trees and shrubs budding out .  Most of the herbaceous perennials had survived, but they didn’t increase in size during the summer. They hardly bloomed.  They didn’t die.  They just sat there.  Watering seemed to make no difference.

I figured that the larger plants (trees and shrubs) were able to get their roots down into the clay where there was more moisture and more nutrients.  But the perennials were struggling with their smaller root balls being mostly in the 8-10 inches of sandy loam topsoil.  Here water drained away quickly and despite the wood chip mulch, the unrelenting sun and high temperatures baked the soil to an iron hard cap over dull powdery stuff below (if you could get the spade in that far!).

I had a soil test done by the soil laboratory at CSU which told me that our topsoil was low in nitrogen and organic matter.  Ah-ha!  That is why the plants weren’t thriving.  The lack of nitrogen was slowing the development of stems and leaves.  The lack of organic matter meant the soil wasn’t holding sufficient water for the plants’ roots to take up.

OK, I thought, we have to do more to improve the soil. I’ve never liked the idea of just throwing chemical fertilizers at the garden.  It’s expensive, wasteful and potentially dangerous to the wider environment.  Double-digging and adding store-bought amendments (of uncertain quality) is back-breaking and expensive. What to do?

Soil is not tilled in the natural world.  Fertility is built up by the decomposition of leaves, twigs and other plant waste on the surface.  Soil texture and nutrient levels are also improved by the actions and decomposition of organisms living in the soil and plant roots.  I’d just been reading about permaculture gardening techniques and the soil improvement technique of “sheet composting” or “lasagna gardening” seemed to be what we needed.

This is a way of building up organic matter and nitrogen in the soil without digging.  You gather different sorts of compostable material (green garden waste, compost, grass clippings, straw, dried leaves, well-rotted manure are just some you can use) and pile them up on the soil in layers.  Hence “sheet” composting or “lasagna” gardening. Essentially, you are making compost directly on top of the soil rather than in a compost bin elsewhere and then transferring it later to the garden.

Many books suggest that you also lay newspapers or plain cardboard down first to smother any existing weeds in the ground.  This is usually where you are trying to improve a weedy, uncultivated area.  But such two dimensional materials can be a barrier to the passage of water, nutrients and the essential soil creatures (see below) that you need to make the process work.

Cardboard layer to start

Cardboard layer to start. Existing wood chips raked on to path first.

Cardboard often incorporates waxes which inhibit the movement of moisture and make it hard to break down.  Shredded newspaper in half inch layers may be a better alternative, but not perfect.  I did use cardboard, but in hindsight probably didn’t need it as the soil was not weedy at all.

Every layer has to be thoroughly soaked with water including the existing soil.  The fungi, bacteria, insects, beetles, earthworms etc. that will break down your materials need water to do their work.

My “recipe” comprised from bottom (soil level) to top:

  • cardboard (on reflection, probably not needed)
  • garden compost (precious stuff from my own bins)
  • grass clippings from a neighbor’s “pile” and half a bag of left-over peat moss
  • partially decomposed garden waste from another neighbor’s “pile”
  • wood shavings and straw from another neighbor’s old chicken shed
  • grass clippings again
  • leaves collected in our leaf cage from the previous fall
  • more partially decomposed garden waste
  • wood chips to hold it all in place and for aesthetic appeal

The layers amounted up to about 12 inches of material.  Each layer was watered in.  Grass clippings were laid in approximately 1 inch layers while the other materials were laid in 3-4 inch layers.  You need much more brown material by volume than green.

Straw and partially decomposed garden waste

Straw and partially decomposed garden waste

Just like making compost conventionally it is important to have a mix of “green” and “brown” materials or, in chemical terms, sources of nitrogen and carbon.  Too much green (e.g. grass clippings) and you have too much nitrogen.  Too much nitrogen will encourage leafy top growth in your plants at the expense of root and fruit/flower development leading to straggly unhealthy plants.  Too much brown and the materials won’t break down sufficiently.

But the green/brown or nitrogen/carbon balance isn’t just about your plants.  All the living creatures in your soil need the right balance too.  They have to live, multiply, work the soil, die and decompose in order to release the precious nutrients to your plants.  The soil creatures need to feed before your plants can.

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Last year’s leaves go on

It’s important that the materials you bring in don’t also bring in weed seeds resulting in a huge weeding problem for the next year.  But the theory is that any weed seeds that do come in will rot in the damp condition of the layers. And if they don’t rot first, they won’t germinate anyway due to lack of light.

The biggest part of this job is sourcing and gathering all the materials.  There were many trips to neighbors’ gardens with rakes and shovels.  Then the trips home again with a car full of other people’s “waste” in old plastic bags. It is hard work.

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The finished thing

So, now we have some 60 feet of garden borders resting for the winter under their layers of composting (we hope!) materials.  We also have many other areas where fewer layers were used (mainly straw with grass clippings or partially decomposed garden waste) to about 3-4 inches to perk up the soil around and between trees and shrubs.

Many questions remain:

  • Will the cardboard decompose?
  • Is the “green” and “brown” balance right?
  • Will the raccoons and skunks churn it all up?
  • Will there be a crop of new weeds from the imported materials?
  • Will the cold Colorado winter simply stop any decomposition from taking place?
  • Will there just be a smelly slimy heap to remove next spring?
  • OR, will we have achieved that elixir of gardening – fertile, well-drained, moisture-retentive soil???

Well, the answers to all these questions will be given next year when I report back in another post.

In the meantime, what do you think? Have you tried this? Did it work well? Please share your comments below.

Anne Hughes  – Denver County Apprentice Master Gardener

Fall in the Perennial Garden: The Case for Less Clean Up

Mid Summer BorderI don’t know about you, but in my perennial garden, fall cleanup can be hit or miss. Whether a function of limited time, gardener burnout or an early cold spell, some years I just let it all freeze dry in place till the spring. What I’ve found is there are some really good reasons to do less fall clean up and I’m not as lazy as I once thought.

Here’s the case for leaving most perennial flower garden cleanup for the spring:

  • Dried foliage will help protect the crown of perennials from the freeze/thaw cycle; this is especially good for marginally hardy perennials. If  you decide to prune, leave about 3-4 inches from the ground to avoid damaging the crown.
  • Dead stems “mark” the plant and lessen the chance of accidentally digging it up or stomping on it in the spring. This can be really helpful for plants that wake up a bit later each spring (Threadleaf Coreopsis does this in my garden).
  • Plants may drop seeds and give you additional seedlings to love or give to friends next year. Such was the case with the Black Eyed Susan’s/Goldsturm Rudbeckia in the photo above.
  •  Seed heads provide tasty food for birds.
  • Enjoy the natural beauty of the winter landscape such as the ornamental grasses moving in the wind and the various colors and textures of foliage, which can be especially lovely when covered with a dusting of snow.

Bright pink Salvia Greggii /Wild Thing Sage. This semi-woody plant should be pruned in the spring. Photo courtesy of PlantSelect.org.

  • Some plants highly prefer spring pruning, such as grasses and plants with semi-woody stems such as Munstead Lavender and  Wild Thing Sage or Salvia Greggii. A spring haircut when new growth emerges often yields a plant with better form and growth. (Not to mention increased chance of winter survival).
  • Early season flowering shrubs such as lilac have already put on the growth that produce next year’s flowers. If you cut now, you will not have blooms next spring. These plants should be pruned soon
    Lilacs which were side pruned too late in the season. Photo from CSU CO Master Gardener Garden Notes #616
    Lilacs which were side pruned too late in the season. Photo from CSU CO Master Gardener Garden Notes #616

    after they are done blooming. A good general rule for lilacs is prune no later than July 4th.

Now, having said all that…here are beneficial fall care tips:

  • Cut back overly assertive perennials whose seedlings take over the garden and become a nuisance. Denver Gold Columbine and Walker’s Low Catmint are prime examples in my garden.
  • Remove leaves of plants that had powdery mildew or other foliage diseases. This will cut down the chance of the problem festering in the soil and re-emerging next spring.
  • Trim long rose canes  which can get damaged by the wind, otherwise don’t prune roses.
  •  Apply light mulch after plants have gone dormant, usually after a few hard freezes. Avoid packing mulch down too tightly so that beneficial moisture can reach the plant and the mulch does not spawn mildew or mold.
  •  Water during dry spells.  When there is little fall/winter precipitation  give the landscape a drink once a month, when temps are over 40 degrees and as early in the day as possible.

Personal preferences vary, so do what’s right for you. Just don’t beat yourself if you kick up your feet and leave most of the chores till the spring!

References for this post:

Winterizing Perennials, Plant Talk 1020

Maintaining Perennials, Plant Talk 1019

Winterizing Perennials During Drought, Plant Talk 1064

Written by Linda McDonnell, Denver County Master Gardener

Pass-Along Plants

Many plants in my garden came from the gardens of friends.  I call these pass-along plants.
The Ginnala maple in my back yard is turning red and today the leaves are blowing off. This tree came from Virginia’s yard as a “stick” not quite 1 foot tall.  I managed to over-winter it for a few years on my back porch, moving it to a larger pot as needed.  Now it provides a hiding place and a launching pad for the little birds that eat at my bird feeder.  Ginnala Maple
Also in my back yard is the rhubarb plant that Patti brought back from her parents’ farm in Iowa.  It has done well here, in Denver.
The walk to my front door is lined with Maximilian sunflowers. These tall, happy perennials came from Jane’s yard. They tend to spread on their own, which makes them a good pass-along plant.
Perennials that spread and self seeding annuals are wonderful gifts if the giver warns the next gardener about the plant’s habits.

The story of the pass-along plant can live on after both gardener and garden are gone.  Take a minute to remember or to plan the pass-along plants in your garden.