Colorado Gardening Calendar for January 2024

Early January at the Denver Botanic Gardens Photo: Linda McDonnell

By Linda McDonnell, CSU Extension – Denver Master Gardener since 2013

It may be tempting to kick back and think there is nothing much to do in the garden this month. And while it is not the busiest time, taking a few steps when needed will set plants, trees, and lawns up for future success.

Winter Watering – January’s Most Important Task

It’s important to water trees, shrubs, perennials, and lawns during extended dry periods of 2-4 weeks. Supplemental water provides root systems with moisture that is critical to long-term plant health. It is especially crucial for new plants (1 year old or less) with smaller, less developed roots. Without this added moisture, plants may exhibit stunted growth, be more susceptible to disease, or die. Often decline is not noticeable till next summer when the root system can’t support the plant’s vigorous growth.

Water early in the day when temperatures are above forty degrees. Give plants a good soak – 8 to 12″ deep and out to the drip line of trees. Find more information on winter watering here.

Branches of  ‘Carol Mackie’ Daphne will easily split under heavy snow. Photo: Linda McDonnell

Trees and Shrubs

Heavy snow can crush or bend the limbs of trees and shrubs. Remove it by lifting branches lightly from the bottom with a broom to avoid breaking limbs. The branches will spring back as if to say thanks.

Prune any storm-damaged limbs as needed to prevent further breakage. Find additional post-storm tips here.

Perennials

Watch for signs of heaving such as cracked soil and raised crowns. This can happen around newly planted perennials when temperatures fluctuate widely. Heaving can expose and damage roots and kill plants. If heaving is present, check moisture, add soil or compost around the plant, and top with mulch.

Speaking of mulch – spread more where needed; it will help moderate temperature extremes.

Remove any diseased foliage that’s lingering in your beds to reduce the chance of infesting next season’s growth. Discard the foliage in the city’s green compost bin or trash. Home compost systems don’t get “hot” enough to destroy pathogens.

Plan Ahead

Should you keep or toss old seed packets? Learn how to tell here.

Scour online and print catalogs to find tried-and-true plant varieties along with new, buzz-worthy introductions.

The CSU Soil Testing Lab opens on January 21^st. If the ground is workable, consider beating the spring rush and sending a sample for analysis this winter. Find directions for digging the sample, using the results and costs here.

Check out the line-up of CSU’s no-cost webinars. There are lots of topics to choose from including turf alternatives, CSU test garden results, and water-saving tips. Find the full spring schedule and recordings of past webinars here.

Explore CSU’s resources for research-based gardening information that will make this year’s garden the best one yet.

Experimenting with Winter Seed Propagation

By Lori Williams, CSU Extension – Denver Master Gardener since 2016

 I hope my winter experiment yields beautiful Echinacea plants this summer! Image: Flickr

I’m a fan of the gardening podcast “A Way to Garden” hosted by Margaret Roach, columnist for The New York Times. Recently she interviewed Heather McCargo, founder of the Wild Seed Project, a horticulturist-supported non-profit based in Maine. The organization is committed to building awareness of native plants, the importance of increasing biodiversity, and ethical seed collection. Find the full interview here.

Their discussion of outdoor winter seed sowing really piqued my interest. Had I ever given much thought to winter sun, precipitation and temperatures being necessary for native seeds to germinate? Honestly? No. 

The suggested timing for winter seed propagation – start after the holidays – also caught my attention. It all sounded pretty simple. Start by gathering on-hand garden supplies and seeds collected from my yard and other gardeners and find an appropriate winter location for the pots to live. The genuine bonus of growing a few of my own perennials was just too intriguing not to try. I was inspired!

Everything needed for winter propagation of seeds that not only survive winter but germinate because of winter. Photo: Lori Williams

Materials

• Containers roughly 4-8” wide, avoid biodegradable pots as they will likely break down in winter weather.
• Seeds – discover germination guidelines and other seed information for Colorado here.
• Organic, compost-based potting soil is recommended because it’s filled with different microorganisms. Please note, compost is not recommended for Colorado native plants as they prefer a ‘leaner,’ less organic soil. Find info on propagating our regional natives here and in CSU’s fact sheet 7.242.
• Coarse sand to cover seeds after planting assists seeds in staying lodged in planting medium and allows light to reach them.
• Group containers, flats, etc. and cover with wire screen, anchored with bricks or rocks, for squirrel protection.
• Label pots to avoid forgetting what seeds were planted where. Pencil on plastic tags really does work best.

January 17th was 38℉ & partly cloudy, a cold breeze bringing in a big snow, I wanted my seeds to benefit from the predicted precip. Photo: Lori Williams

Location

• A level, shaded area for containers to endure winter undisturbed. Shade is essential during sunny, warm days so pots don’t overheat and dry out. Keep containers level so seeds don’t float or splash out during heavy precipitation.

Ethical Seeds

The Wild Seed Project stresses collecting and using seeds native to your location. Collecting native seed from public lands and in the wild (in Maine, Colorado, and most of the nation) is typically a huge no-no (AKA unethical) so how do we collect seeds ethically? 

• Seed from our own gardens are the easiest to collect. 
• The friendly approach of asking ‘May I gather a few seeds from your XYZ perennial? I’d love to try to grow it.’  
• Seed swaps are another excellent resource and a request on social media can produce great results. 
• Wild Seed Project and other ethical seed providers offer native seeds for purchase. 

Buy seeds suitable to your growing conditions, of course, and be familiar with what those plant seeds look like. As a newbie gardener, I planted dried Echinacea flower petals twice thinking they were seeds. 

My Project

While I did not have native seeds for my backyard experiment, I did have ethically collected seeds from non-natives. I planted three flats with Echinacea and lavender seeds from my garden and seeds from a divine lupine that was a volunteer in a friend’s yard. On January 17th I placed my pots in deep shade against the house with bricks holding the screen cover in place. That evening 6.5” of snow fell and temps stayed cold for weeks afterward. 

Snow covered since January 17^th, it took the snow on my flats until the end of February to finally melt. Photo: Lori Williams

Outdoor winter propagation is challenging for the impatient gardener (me) but my long game of possibly growing some perennials of my own from seed has me hopeful. With more Colorado snow and cold ahead, my flats remain undisturbed in the shade. I resisted the urge to water them during the last several weeks of no moisture – and then we had a welcome icy rain turning into snow – YES! 

As my flats have yet to show any noticeable growth, I am watching for signs of success during our longer days accompanied by the sun beaming from higher in the sky. 

Colorado Gardening Calendar for March 2023

By Valerie Podmore, CSU Extension-Denver Master Gardener since 2020

These Tulips have restored my faith in spring and gardening! by Valerie Podmore

I have a confession to make. I have not been thinking about the garden much this past winter and almost thought (dare I say it) I might just pack the whole thing in. However, my eye was caught this morning by the sight of tulips starting to pop through the soil and it made me happy, and I think I have caught the bug again! So, let’s see what we can do now that we are starting to see more sunshine, and the days are getting longer. MARCH is one of the best months to prepare for the upcoming growing season, so mark your calendar to get these gardening to-do’s done in your yard and garden.

Vegetable Garden

This year I am determined to try raised bed gardening and am beginning to research what it takes to succeed. Maybe we can learn together!

• I’m starting with this article to help me figure out what to plant as a new veggie gardener.
• The raised bed method of gardening is explained in depth here. I must work to not get overwhelmed by the wealth of knowledge!
• If you are like me and have delusions of veggie growing grandeur, you will possibly have more seeds than any normal human should be allowed to have! Many of these are probably no longer viable, so best to inventory your seeds and order any you might still need.
• Last week’s post about seed starting is a timely and great way to educate ourselves on starting our plants using the DIY method.

Trees and Shrubs

• Since we’ve had so much snowfall (we’ve certainly needed the moisture!), supplemental watering is possibly not needed, but anything can happen in March so remember to water your trees and shrubs if there’s a drop-off in precipitation.
• This is a great month to prune trees and shrubs for those who want to get outdoors and “DO SOMETHING!”

Lawn Care

• If you love late winter/early spring lawn and garden care (who doesn’t love a good spring clean?) there are great suggestions in this article.
• Early March is a great time to sharpen up your mower blades and add or replace oil, clean shovels and pots, and generally tidy up anything that has been languishing in wait for warmer days.
• Late March is a great time to start aerating as long as the ground is not frozen.

Perennial/Annual Flower Beds

• While most of our garden isn’t completely awake yet, we can still take stock of what plants worked last year and what we’d like to fill in this year.
• That brings us to seeds and bulbs! See what bulbs you’ve got that can be replanted from storage; what seeds can be sprouted indoors.
• If you attended the Colorado Home and Garden Show last month (probably good that I didn’t, as I would become way too over-ambitious!), use any ideas you gained for changes you want to make.

Don’t forget to visit the CSU Extension Yard and Garden website (https://extension.colostate.edu/topic-areas/yard-garden) for more gardening tips, and yay spring!

Starting Seeds Indoors for Your Vegetable & Flower Garden

By Molly Gaines, CSU Extension-Denver Master Gardener since 2019

I became obsessed a few years ago with growing luffa sponges (Luffa aegyptiaca). I remember my grandpa growing them in Iowa, proudly tending the massive vines with long green squash, harvesting them by the bushel, peeling and drying them. But I’ve never seen luffa seedlings in Colorado, so I found my seeds online through a specialty seed website and started them inside. Luffas’ long growing season isn’t very conducive to our Colorado climate. If sown directly into the garden, they’d never mature before the fall frost.

Reasons to Start Seeds Indoors

Plants that grow best from a seedling, versus direct sowing, are the best candidates for starting inside. Focus on plants that require a longer grow time until harvest, such as heat-loving varieties. Starting seeds indoors also allows for more variety beyond what you can find in gardening centers. It also allows for more control over the early growth stages.

Cost savings is another benefit to starting seeds inside. Once you’ve invested in some supplies, it’s more economical than buying seedlings at a nursery.

Luffas require at least a 90- to 120-day growing period, so these plants are best started indoors in Colorado. Photo by Molly Gaines

Timing & Desired Plantings

Plant seeds indoors 4-8 weeks before the last spring frost date (see Growing Plants From Seed), generally considered May 5 in Denver. Review the back of seed for time to harvest. If a tomato variety requires 90 days to harvest, start the seeds inside by early April to begin harvesting in July.

Keep in mind, not all varieties tolerate being grown inside and then transplanted. Carrots, for example, do best sown directly into the garden bed.

I mostly stick to starting seeds for heat-loving vegetables and herbs that take longer to mature — cucumbers, tomatoes, some herbs and squash. As mentioned before, I also consider what varieties I can find at CO garden centers vs. varieties available only if I start the seeds myself.

Happy, thriving seedlings. Photo by Molly Gaines

Seed-Starting Supplies & Tips for Growing

Consider these supplies and growing tips:

1. Seedling containers, pots and/or trays and clear, plastic covers. I like the plastic trays with individual cells or small compostable pots. A quick Google search will also show many DIY options. Covering trays with an elevated plastic lid during germination is very helpful. Use the lid only when your trays are not in the sun or under light to avoid overheating.
2. Lighting. I plant my seedlings near a sunny window. But an overhead light, on for 12 hours a day, is best for strong, vs. leggy, seedlings. Lighting should be adjustable, always hanging about 2-inches above the plants.
3. Seed-starting mix. Usually a blend of perlite, vermiculite and peat moss/coir vs. actual soil; it needs to be loose and fluffy. When planting, poke seeds into the mix at a 1/4-inch depth.
4. Labels. Label seedlings so you can remember what was potted where.
5. Water. Keep a cup and/or spray bottle near your seedlings for spraying during germination and watering. Seeds and seedlings must be kept damp.
6. Heat. A seedling heat mat speeds sprouting. The growing medium should stay between 70-80 degrees Fahrenheit.
7. Fan. Good airflow helps prevent disease. It also helps create stronger stems.

I like this type of seed-starting medium that expand with water. Photo by Molly Gaines

Feed and Repot

You can fertilize, as needed, once the first set of true leaves on seedlings emerge. Use a diluted solution. Mix according to the fertilizer label then dilute by 1/2 or a 1/4. Don’t overdo it. If your seedlings look healthy, fertilizer isn’t necessary.

Harden Off Before Transplanting Outside

Gradually introduce seedlings to the outdoors. “Harden off” your seedlings, taking them outside and bringing them back inside for 5-7 days, each day leaving them out longer. Place trays or pots in a shady spot. Keep them well-watered.

Speaking of transplanting outside, next time I grow luffas I’ll either start them inside sooner, or plant them outside earlier. While I had a lot of fun tending to my luffas, particularly seeing the gorgeous big yellow flowers blossom (the bees love luffa flowers!), many of the gourds didn’t fully ripen. The ones that did made fabulous holiday gifts, and I loved telling people the story behind them.

My luffas, my pride and joys! Photos by Molly Gaines

Additional Seed-Starting References and Resources:

Seed Starting webinar (2022), CSU Extension, Larimer County

Starting Seeds Indoors

Vegetable Planting Guide

Colorado Gardening Calendar for January 2023

By Linda McDonnell, CSU Extension – Denver Master Gardener since 2013

January is typically a restful period for gardeners – a  time to pour over seed company websites or catalogs, review last year’s successes or blunders, set goals for the upcoming season, and investigate new gardening topics. But even though we may be ‘armchair gardening’, it is important to keep a watchful eye for issues that crop up in the landscape. Don’t forget to occasionally stroll through the garden, especially after storms, to inspect trees and plants. Take care of any issues as soon as you’re able to avoid complications later.

It’s a cold and snowy start to the new year!

Let’s take a look at recommendations for the month.

Trees and Shrubs

• We’re huge proponents of winter watering, but thanks to a sloppy, moisture-rich late December snowstorm, watering may not be needed in January. This could begin to change later in the month though, so monitor conditions with special attention to new plantings. Four weeks without sizeable moisture is the signal to drag the hoses out.

• Regularly examine trees and shrubs for snapped limbs and bark damage due to snow loads or heavy winds. This post offers tips on preventive maintenance and dealing with damage.

• Winter is an ideal time to have large deciduous trees pruned professionally. The City Forester maintains this list of licensed contractors; pointers for hiring a tree care company can be found here.

• De-icing salts used on nearby sidewalks can cause leaf scorch on evergreen broadleaf shrubs, brown needles on conifers, and damage to turf roots. Use with care.

Manhattan Euonymus (Euonymus kiautschovicus) is a broadleaf evergreen shrub prone to leaf scorch Photo: Linda McDonnell

Perennials

• Add additional mulch around perennials that are heaving or lifting up from the soil. Heaving is caused by repeated freezing and thawing, often occurs in newly planted perennials with young root systems, and can indicate compacted soil. Left unattended, it can damage or kill plants. Come spring, organic matter may be needed to improve drainage. According to the University of Iowa, shasta daisy, (Leucanthemum spp.) and coral bells (Heuchera spp.) are particularly prone to heaving.

Pixabay.com

Seeds

• Take stock of your seed stash – the prior season’s seeds may still be viable. CSU’s fact sheet on storing veggie and flower seeds has a helpful chart on seed longevity.

• While it is still a bit early to start seeds indoors, it’s not too soon to replenish seeds and supplies at a local garden center or online. Or set up a seed swap with your gardening buddies.

• If you’re new to seed starting or want a refresher, check out this blog post for a thorough tutorial so you are ready to go when it’s time.

Denver’s Recycling and Compost Programs

• Denver’s ‘green cart’ compost program rolls out citywide this month. Meat and produce scraps, coffee filters, and greasy pizza boxes, in addition to garden waste, are just a few of the tossable items. If you already participate in the program, be sure to encourage green cart newbies to give it a try.

• Have old, unused, or unwanted pesticides or herbicides hanging around? Here’s info on Denver’s program for the safe disposal of many hazardous materials  A nominal fee applies.

 Learning Opportunities

• Managing Squirrels in the Landscape on January 11th from 12-1 pm is the first in CSU’s series of virtual garden workshops. For a list of all presentations and to register, visit https://csuhort.blogspot.com/p/csu-extension-spring-gardening-webinars.html.

• The Colorado Garden & Home Show returns to the Colorado Convention Center February 4-12^th.  In addition to workshops, extensive plant displays, and vendor information, Colorado Master Gardeners will be present to answer gardening questions. Tickets available now.

• Audubon Rockies and Cheyenne-High Plains Audubon Society hosts the Landscaping for Water Realities on the High Plains conference on February 4^th.  Virtual attendance is free. Program and registration info here.

• Email garden and plant questions with descriptive photos to Denver Master Gardeners at the Denver Botanic Gardens gardeninghelp@botanicgardens.org.

• CSU’s Extension website is always available to provide science-based gardening information. It’s a good one to bookmark.

Colorado Garden Calendar – December 2022

Photo: Jodi Torpey

By Linda McDonnell, CSU Extension – Denver Master Gardener since 2013

Gardening slows down in December but doesn’t stop completely. There’s still time to finish some chores from our November list, so be sure to revisit it. For the next few months, prioritize winter watering during dry spells to ensure healthy plants next year.

December’s also a great time to enjoy indoor plants, appreciate nature’s seasonal beauty, and start thinking about next year’s garden.

Here’s a run-down of tasks and activities for December.

Trees, Shrubs, and Perennials

• Winter watering is essential to long-term plant health – make it a point to water during four-week dry stretches. To ensure proper absorption, water early in the day when temperatures are above forty degrees. This post offers excellent advice on when, why, and how much to water – and photos of the impact of too little moisture.
• To help with moisture retention, replenish mulch in areas that have gotten thin.
• Shake snow from bent tree limbs and branches to avoid breakage and lightly prune any broken limbs to avoid further damage.

Compost

• Continue adding green and brown materials to your compost bin. Since decomposition is slower in cold temperatures, break your materials into smaller pieces to speed up the process. The University of New Hampshire offers more winter composting tips here.

Thanksgiving cactus approaching its fourth decade & going strong. Photo: Linda McDonnell

Houseplants

• Winter is the dormant season for non-blooming indoor plants. Reduce watering, stop fertilizing, and keep them away from drafts for the next few months.
• Increase humidity around your plants. Ignore popular advice to mist with a spray bottle – to make an impact you’d need to mist for hours on end! Instead, group plants together on a pebble-lined tray and add water to just below the top of the pebbles.
• Check regularly for pests such as mealy bugs and spider mites. If present, treat and quarantine the infected plant. Find remedies here.
• ‘Tis the season for holiday plants and live Christmas trees. Here are some helpful links to keep them at their best: Keeping the Ho Ho Ho in Holiday Plants, Tips for Caring for Your Christmas Tree, A Year in the Life of an Amaryllis, and Christmas Cactus Care.

Celebrate, Inspire, and Explore

• The winter solstice arrives on December 21^st. In the Northern Hemisphere, it marks the day when the sun is at its lowest height at noon as well as the shortest day of the year. Starting the next day, we’ll gain about two minutes of daylight daily till June 21^st. Yippee!
• Share your enthusiasm for gardening with a child – find a few activities here or wander the library aisles to find an inspiring book on plants or nature.
• Check out 2023 seed introductions from your favorite growers. It’s time to start scheming and dreaming about next year’s garden.

As always, CSU is available to help with gardening advice at the CSU Extension Yard and Garden website. We hope you’ll visit often.

We’ll be back in two weeks with our last post of the year. Until then, enjoy all the season brings.

Seed Saving, Part 2

By Jessica Harvey, CSU Extension Denver Master Gardener since 2020

Welcome back to the second installment of seed saving, where we’ll continue discussing saving wet versus dry seeds as well as cleaning and storing techniques. If you missed the first part last week, scroll down and read about the different types of plants, their growth cycles and types of pollination—all great things to consider when planning which seeds to save from your garden. 

Wet or Dry Seed

Now that you’ve decided what to save it’s time to consider the type of seed, whether it’s a wet or dry seed. Wet seeds are those that will need to be separated from the fruit flesh like tomatoes, peppers, squash or cucumbers. Dry seeds will only need to be separated from their pods or flower heads after being allowed to fully dry out like peas, beans, herbs and most flowers. 

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  Dill seed ready to harvest by Jessica Harvey

When saving wet seeds, it’s best to let the fruit overripen to ensure the seed is mature. Pull fruit from the vine long after you’d normally do so, but before it has a chance to rot. For dry seeds, leave the pods on the plant until they’ve fully dried out or the seeds are already starting to drop. It’s best to snag these seeds before the wind does though, trim and drop in a paper bag to continue drying out for easy harvesting.  

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  Cleome seed pods by Jessica Harvey

Some seeds require extra steps in order to save. Tomato seeds have a gel coating around each seed which acts as a growth inhibitor. Without that coating you’d start growing tomato plants straight out of your tomatoes! To remove this gel, you’ll need to briefly ferment them. Scoop out your seeds and place in a cup with water on the counter for several days or until a film of mold forms along the top. Skim the mold off and rinse the remaining seeds several times until only seeds remain in clean water. Discard any seeds that float as mature seeds should sink.

Make sure to set these wet seeds out on a paper towel or coffee filter in order to dry for a few days before storing. You may also consider getting some silica from your local hobby supply store to add to your envelopes to help draw out any lingering moisture. If you notice mold or discoloration of any seeds separate and dispose of them, don’t risk contaminating your whole harvest.

Many dry seeds will need additional cleaning to remove excess plant debris that may have been harvested with the seeds. A brightly colored tray works great for this as it’s easy to see the dried flower parts and separate your seeds. The less excess chaff you save with your seed the easier it will be when sowing in the spring. 

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  Collecting and cleaning Celosia seed on a tray by Jessica Harvey

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  Separating seeds from plant debris by Jessica Harvey

From there you’ll want to store your seeds in a cool, dark place. It’s best to use paper envelopes over plastic, mold can form in plastic but the seeds will continue to dry in the paper. Another important step is to label your seed so you don’t forget what it is you are saving! Best practice is to record the plant information and year for future reference. If you are planning to share your seed you can also include your name or zip code. Many seed libraries will ask for information like zip code to record with the redeposit of seed for future use.

For more information on Storing Vegetable and Flower Seed check out CSU Extension Fact Sheet 7.221 and PlantTalk Colorado’s article 2020-Seed Storage.

Happy seed saving, and if you’re anything like me, seed hoarding!

Seed Saving, Part 1

By Jessica Harvey, CSU Extension Denver Master Gardener since 2020

You may think it’s a little early to be thinking about saving seeds, but many plants will start going to seed in the coming weeks and it’s best to plan in advance. With a plan in place, you won’t miss out on saving some of your garden favorites! 

Saving seeds is a great way to build hardiness and local adaption into your plants. Plus, saving seeds allows you to share within your community. There are many local efforts aimed at promoting seed saving and sharing, like the Denver Local Seed Project and Rocky Mountain Seed Alliance. 

As you start to consider which seeds you plan to save, it’s important to consider the type of plant, growth cycle and method of pollination. From there we can plan the harvest based on whether it’s a wet or dry seed. Let’s break it down in this two-part blog and if you are unclear of any of the terms used below check out these seed-saving, gardening terms from Seed Savers Exchange: https://www.seedsavers.org/seed-saving-gardening-terms

Type of Plant

Is your plant a hybrid or heirloom/open-pollinated? Hybrids are typically noted with F1, meaning first generation, on the seed packet and are often patented. Hybrid seeds are purposefully bred for certain traits and won’t come true from saved seed because of this. Heirloom and open-pollinated plants, however, will come true to seed and are your best bet for saving. 

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  Johnny’s hybrid seed packet. Photo by Jessica Harvey

Growth Cycle

Is your plant an annual, biennial or perennial? Annuals and many perennials will produce seed within one season; however, biennials take two seasons before producing seed. Common examples of biennials are root vegetables like carrots, radishes and onions. In order to save seeds of these types of plants you’ll need to leave them in the garden for a second season; or you may even have to dig the first-year plant and overwinter it indoors and replant again the following year. 

Check out CSU Extension Fact Sheet 7.602 – Saving Seed for a quick list of biennial vegetables:

Type of Pollination

The method of pollination may impact what you decide to save as well. The primary types of pollination are self, wind and insect-pollinated. 

Self-pollinated plants include tomatoes, peppers, lettuce, beans and peas. They are often the easiest to save without worrying about cross-pollination between different plants. Sometimes referred to as self-fertile, these plants have everything they need to produce seed without another plant. Insects may still visit them, but the odds are seed will come true once saved. 

Wind-pollinated plants include corn, spinach, beets and Swiss chard. They rely heavily on mother nature and multiple plants of the same type within a certain distance. Since these plants rely on pollen to travel, if there are any other cultivars or plant family members within the isolation distance, you may end up unintentionally breeding something completely different then intended. Isolation distance refers to the recommended distance between cultivars or different species in order to be sure cross-pollination is not occurring. 

Insect-pollinated plants include squashes, melons, cucumbers, cabbage and kale. They are much more likely to be crossed without you even realizing for this same reason. Many of us grow numerous plants of the same type or within the same genus. A bee may visit your zucchini and butternut squash plants, both are in the Cucurbit family. You may well save the seed from a zucchini, but when you grow that seed on next season it may have characteristics of both the zucchini and butternut squash.

Many recommend manually pollinating and bagging the flowers and subsequent fruit if you intend to save seed of either wind or insect-pollinated plants. To do this you need to watch for when the flowers first open, then using a brush, manually transfer pollen between a male and female flower before bagging it up to make sure no further pollination takes place. Once the fruit starts to form you can remove the bag and then save seed from that fruit after it reaches maturity. It may seem a little excessive, but it’s the surest way to know your saved seed will come true when you’re growing multiple varieties or species.   

Seed Savers Exchange has a great Seed Saving Guide with information on life cycle, pollination method and recommended isolation distances.

Please make sure to check back next week, in this two-part blog we’ll go on to talk about saving seed whether it’s a wet or dry seed, cleaning and storing techniques. Until then, happy harvesting!

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  Saving heirloom tomato seeds means more juicy Brandywine tomatoes next season. Photo by Jodi Torpey

Indoor Seed Starting for Beginning Gardeners

By Jessica Harvey
CSU Extension-Denver Master Gardener since 2020

^{Pepper plant starts with both cotyledons and first set of true leaves visible. Photo provided by Jessica Harvey.}

We’ve all fallen prey to the allure of seed catalogs during the winter, with their bright photos and promises of plants to come. So what do you do after your seeds arrive?

Before you do anything, consider how much space you have to grow. The expression “your eyes are bigger than your stomach” can also be applied to buying seeds and finding places to plant them. After you’ve narrowed your planting choices, it’s time to get started.

Begin by deciding which flowers and veggies should be started indoors in early spring and which are better suited to direct sowing into your garden. Check seed packets for seed starting information or use a seed-starting guide.

You can grow in just about any type of container, whether it’s a leftover egg carton or a grow kit. The important thing is that it’s clean and free of potential fungi or bacteria. If you’re reusing trays, be sure to clean and rinse several times before using so there’s no residual disinfectant or soap.

Grow kits generally come with a bottom tray, cell tray and a dome. The cell tray will have slits or holes to allow water to be soaked up from the bottom tray. If you aren’t using a kit, you’ll need to create your own that fits the containers you’ll be using. A three-part system will be important as you get started to help bring those seeds out of dormancy.

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  Domed seed starting trays by Jessica Harvey

There are number of inexpensive soil-less media options to choose from. If you want to use a soil-based starter just be sure it’s loose, fine in texture and has good drainage. Seeds need to be kept moist, but not sitting in water.

Once you have your containers ready and filled with your seed starting media, place a couple of seeds in each cell. Best practice is to make a small indent with your finger on the top of your media and lightly cover the seeds as you go. Always check seed packets for planting depth to keep from planting too deeply.

Record as you go. Draw a grid and write in each variety/plant to avoid playing a guessing game later. Note the date as well. If you know when you started, you can gauge when to start these same types of seeds again in future years based on your experience.

Mist or lightly spray the mixture atop your seeds, again moist but not wet. Don’t apply a stream of water or seeds will wash out of the cell. Add a thin layer of water to the under tray to start soaking up into the media. Keep water in that tray throughout the growing process. When your seedlings start to grow and send out roots, they will grow towards it.

Put the three-part system together and create a moist, humid environment to wake your seeds from their dormancy, then wait. Your seedlings will appreciate the humid environment under the dome.

Most seeds also like bottom heat as they get started, especially tomatoes and peppers. You can use a heat mat, but you can also place your container on an appliance or area that stays warm. Keep containers warm until seeds begin to sprout, then move them or turn off the heat mat. If you leave your seedlings exposed to that extra warmth for too long you run the risk of them stretching or getting leggy.

Once seedlings emerge, move them into the light and remove the dome cover. They may still enjoy that humid environment, but you don’t want them to start pushing against the dome. As they continue to grow, you’ll notice a first set of leaves called cotyledon. Don’t be fooled, the cotyledons are false leaves! They help seedlings start to photosynthesize, but they aren’t the true leaves of your plant. The cotyledons will eventually die as the actual leaves start to grow.

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  Cotyledons versus first set of true leaves of a catnip plant start. Photo provided by Jessica Harvey.

You can begin transplanting these plants into individual containers and soil-based media once the first true leaves develop. While transplanting, thin out the seedlings to give them room to grow without crowding. Depending on the seeds, you may have over sown and that cell may now be overrun. That’s okay! Just be sure not to let all those seedlings outcompete one another.

Resources:

• PlantTalk 1840 – Starting Vegetable Seeds Indoors
• CMG GardenNotes 719: Vegetable Garden Hints

Gardening Predictions for 2021

There may have been one bright spot among the gloom of 2020: The pandemic turned out to be great for horticulture. Experts estimate the industry gained 16-20 million new gardeners during the pandemic.

They’re predicting 85% of those gardeners will continue this year.

If that prediction holds true, experienced gardeners will be competing with new gardeners for seeds, plants, potting soil, mulch, tools, accessories and anything else that helps with planting and growing.

Last year seed catalogs, online retailers and garden shops couldn’t keep up with the overwhelming spring demand. More than a few had to shut down their online systems so they could catch up with orders.

Even though companies say they’re better prepared this year, gardeners should plan ahead and order their favorite varieties yesterday.

Backyard, front yard, patio and balcony food growing will continue to engage new and newer gardeners. Those who had some success last season will be anxious to expand their gardens; those who wished they would’ve started last season will get growing this year. They’ll be on the lookout for heirlooms and all kinds of organic options.

Some plants will sell out sooner than others because of special marketing and promotional programs. That’s especially true for the National Garden Bureau’s Plants of the Year for 2021.

Every year the national organization selects and promotes its Crops of the Year plants. The selections are popular, easy-to-grow, widely adaptable, genetically diverse, and versatile, according to the NGB.

The 2021 Plants of the Year include:

Annual: Sunflowers
Perennial: Monardas
Bulb crop: Hyacinths
Edible: Garden beans
Shrub: Hardy hibiscus

Plant Select has three new introductions for this year that include Drew’s Folly Hardy Snapdragon (Antirrhinum sempervirens), Hokubetsi (Helichrysum trilineatum) and Blanca Peak Rocky Mountain Beardtongue. The Plant Select website features a list of retailers that offer Plant Select plants so you can call ahead to check on availability.

Smaller garden varieties are part of All-America Selections winning plants this year. Goldilocks squash and Pot-a-peno peppers are meant for small-space gardens. The AAS’s Gold Medal winner is Profusion Red Yellow bicolor zinnia that’s sure to be in demand.

The Perennial Plant Association selected Calamintha nepta (calamint) as its Perennial Plant of the Year for 2021. A nice rock garden and border plant, tiny white flowers bloom on a bushy low mounding plant that attracts pollinators to the garden.

Houseplants will continue to be in demand to fill home offices and windowsills that have turned into miniature greenhouses. New offerings include plants that drape over pot edges and tiny plants for tiny places.

Pantone’s colors of the year will show up in plants, flower colors, pottery and other garden accessories. Look for combinations of Illuminating Yellow and Ultimate Gray at big box stores, garden centers, the plant sections at grocery stores and wherever else gardening supplies are sold.

New gardeners will continue searching for resources, help and advice. CSU Extension master gardeners will need to be extra-creative when it comes to cultivating community from a distance, encouraging new gardeners to reach out for reliable information and finding ways to reduce the fear of failure for beginning gardeners.

If you have any gardening predictions for 2021, look into your crystal ball and add your forecast here.

By Jodi Torpey
CSU Extension master gardener since 2005
Image provided by Pixabay