Monthly Archives: May 2015

Balcony Gardening – Soil, Light and Plants

French Tarragon 1 year after planting in container

French Tarragon 1 year after planting in container.

Time to plant your balcony garden

Soil for container plants is easy to find. Don’t use “Top Soil”. It is likely to be mostly clay and too heavy for your balcony use. Potting soil (with or without time release fertilizer) will be just fine.

If you buy plants – fit them tightly into the pot.  You will have a nice showy pot and it is unlikely that they will outgrow the space over the summer.  If you plant seeds, don’t put the pot in full sun.  Keep seeds moist until they germinate by covering the pot with plastic wrap to keep the soil from drying out and

How much sun your balcony gets will determine your choice of plants.   Don’t forget reflected light from nearby buildings.  Your balcony may receive direct sun only in the morning, but also receive reflected light from the building next door in late afternoon.  This article lists 5 ways to categorize sun and shade for choosing plants (about 2/3 down into this article is the list). More information is there is you want the details. 

Vegetables:  most container vegetables like full sun but may need shade from reflected afternoon light or direct afternoon sun.  Vegetables need to be checked every day to see if they need water – many will, especially when putting on fruit.   Recommended Container Vegetables are listed by type and by name.

Herbs:  Basil is a standard and will probably need water daily in hot weather.  Try cilantro or a chocolate mint plant.  Most perennial herbs grow well in containers and may survive the winter.  Good choices are  French Tarragon, any of the Thyme varieties, Winter Savory, Chives.  Here is more information about Growing Herbs in Containers.

Flowers:  If you would like to screen the view from your balcony – plant tall annuals.   An 8 inch deep pot is best.  All of these grow easily from seed:  sunflowers, cosmos, morning-glory (add a trellis for it to climb).  Amaranth is a grain ( not very edible) and grows 6 feet tall!  Look for the burgundy variety.

Gardening with Children

One of the great joys of gardening is the opportunity to introduce children to its pleasures.  We want them to be able to experience the thrill of watching what happens when a seed is exposed to good soil, water, and sunlight.  That tiny little seed can become a great big plant, and give something back to you – something to eat, like fruits or vegetables, or something pretty, like a flower.

Children of any age benefit from being outdoors, breathing fresh air, having the opportunity to examine bugs, bees, earthworms, and butterflies.  Some aspects to remember:

Select an area for the child’s garden.  Make the garden area accessible and start small.  Make a map of the garden with the child, seek the child’s input on what to grow.  Quick growers like radishes allow children to see rapid progress.

Keep it short.  Children have a limited attention span, work in different areas of the garden about 10 minutes each day.

Plant seeds or seedlings.  Special child-size garden tool sets are available, but a fork and a spoon are completely adequate for most tasks.  Demonstrate how to make a row and plant a seed, how to dig a hole and plant a seedling.  Then, let the child take over. We are after process, not perfection. Most kids love to get wet and play in the dirt.

Feed the future plant.  Use an organic, slow release fertilizer or compost tea on the plantings.  Explain to your child that this material is like “vitamins” for plants, to help them grow big and strong.

Water the seeds or plants. Water immediately after planting to get things started.  Water gently, just slow streams from a garden hose or a watering can.  As seeds grow into plants, the plants will get thirsty just like people do.  Teach your child to do the “poke test”, stick a finger into the soil and feel for wetness to determine if the soil is dry.  If it is, then water the seeds or plants.

Apply some mulch.   According to author Sharon Lovejoy, mulch is like “earth’s quilt”.  It will conserve moisture, deter weeds and prevent erosion.  Assist your child in spreading hay, straw, or wood chips around plants as they begin to grow.

Weeding.  Explain the difference between a desirable plant in the garden and a weed in terms the child can understand.  Show them examples in their own garden plot.  Use your own judgement in deciding if the child is able to differentiate between weed seedlings and desirable plants.

Deadheading.  For kid humor, what’s not to love about this word.   This is a good teaching moment.  If your child is growing some flowers, as the flowers fade, explain to the child that plants want to make flowers in order to make seeds to make new flowers.  But, if we cut off the old flowers, the plant will make more flowers, to keep trying to make seeds.  Judicious supervision will prevent good blooms from being removed.

Make an insect bath.  There are good bugs in the garden, and they need water too.  Select a drainage saucer from a ceramic or plastic pot or an old, shallow pan from the kitchen.  Put a pile of rocks or gravel in the center of the saucer or pan for the bugs to land upon.  Gently pour water into the saucer or pan so that the top of the pile of rocks or gravel remains out of the water and dry.  Put the insect bath on the ground out of the way, so it won’t be stepped on.  Refill with water when the level gets low.

No room for a garden?  Plant in containers instead.  You can make it a project.  Select several sizes of containers, wash inside and out with soap and water, then rinse.  Make sure the pots have drainage holes, and put a screen of some type over the hole (a small piece of a mesh bag from produce works fine).  Put potting soil in the containers, dampen it, and proceed to plant.  Tend the containers as you would plants in the garden, checking frequently for adequate moisture and sunlight.

This should get you started for spring and summer.  Children are much more likely to eat produce which they have grown themselves, so enlist their help in the kitchen when harvesting begins.

Gardening does not stop in the fall, children can assist in the cleanup after frosts.  Encourage them to plan for next year’s garden, let them help pick out selections when the garden catalogues start arriving in the winter.  Who knows, you just may discover you have started a gardener for life!

by Mary Beth Cooper, Denver County Master Gardener

How to Grow Blueberries in Colorado Gardens

BlueberriesColorado gardeners who fall in love with the idea of growing their own blueberries may be disappointed with the results. There just isn’t enough room on a planting tag for all the information they need.

Even if they carefully follow the basic planting instructions, blueberries need much more than “Full sun, acidic soil (incorporate peat moss or organic matter into soil), good drainage, fertilize in early spring, moderate watering.”

That’s because blueberry shrubs arrive in Colorado from growers in the northeast or the northwest where conditions are ideal for growing the plants. The climate on each of those coasts is significantly different from Colorado’s land-locked and semi-arid climate.

The two main challenges the blueberry planting tags don’t cover are the soil pH problems and the way winter dries out plants in our region.

Both of these problems can be solved, but it takes extra effort.

Thanks to CSU Extension blueberry experiments, gardeners have a proven blueprint for blueberry success.

The experiments, conducted by Joel Reich while he was a CSU Extension Horticulturist, are detailed in a one-hour webinar recorded in August 2012 called Blueberries for Colorado Gardens.

Anyone with online access can view the free program to learn all about the best blueberry varieties to plant, where to find them, how to plant and fertilize them, best practices for winter protection and how to keep birds and deer from getting to the juicy fruits before gardeners can enjoy them.

The blueberries growing in CSU’s trial gardens in Longmont show that if gardeners plant in sphagnum peat moss and provide special winter protection, they can enjoy fresh blueberries season after season.

Joel grew blueberries in the trial garden for more than 16 seasons in the same bales of peat moss. He devised a fertility maintenance program with a special combination of acidic fertilizers to use on a May, June, July schedule.


Best practices for planting blueberries mean planting directly inside the sphagnum peat moss bales. The bags are opened only part way to help retain moisture. Holes in the bottom of the bag provide drainage. Drip irrigation is important to make sure the soil stays consistently moist.

The bags are placed in trenches so they’re at grade level, but they could also be placed in a raised bed. Gardeners could grow plants in patio or balcony containers if they select the blueberries classified as “half-high.”  Plants growing in containers will need even more protection from wind in winter.


The key to providing winter protection is to prevent the damage caused by dry weather, low humidity and winds. It’s especially important to wrap or cover each plant so winter winds can’t suck the moisture out of the dormant buds.

The blueberry shrubs need to be wrapped in layers of burlap with the branches tied up and together. An alternative is to cover each plant with a trash barrel that’s weighted down.

By Jodi Torpey

Early May in the Garden

poppy pair

Early May brings us the beauty of iris, the  continuation of tulips and the grace of the shade loving Bleeding Heart. As of May 5th,  we are past our 10 year average final frost date. Even so, many gardeners watch evening lows for the next week or so before putting out tender plants such as basil, tomatoes and many annuals. If worried about a plant in your yard, a good tip is to cover it with a bucket or sheet. A light dusting of snow generally doesn’t cause harm; in fact, it serves as an insulator.

Now is a good time to evaluate your perennial beds.frontgarden

  • Will there be early, mid and late season color?
  • Would some plants do better in another area?
  • Is there an interesting variety of spikey, round and open faced flowers to create visual interest?
  • Do you have a mixture of foliage, color and shape?
  • Are there areas that are too sparse or too crowed?

All of these elements contribute to an interesting, informal, season-long garden. “Perennials sleep in the first year, creep in the second year and leap in the third”, is a common garden adage to keep in mind when designing a garden bed.

The Plant Select brand of plants, which are tested for success in our climate by Colorado State University, the Denver Botanic Gardens and the Colorado landscape industry. Given the wide array of  these plants, you are likely to find many to fill your needs. Check for information on plants and creative garden design layouts.

We hope you’ll join us for our  Denver Master Gardener Plant Sale  for an  amazing array of veggies, herbs, annuals and perennials (including some Plant Select varieties). Stop by on Saturday, May 16th from 8-3 or Sunday, May 17th from 10-3 at the Denver Extension office, 888 E. Iliff Avenue. Here’s a small sample of the gems our Master Gardeners are growing:

  •  Lemon Cucumbers – yellow, round and sweeter than classic types. A new one to try.
  • Pumpkin on a Stick or Tree Pumpkin – a bright and curious ornamental that is long lasting in a vase. Fun for kids and adults alike.
  • Tomatillos – easy to grow plant produces lots of fruit for your authentic salsa.
  • Silver Fur Tree Tomatoes – Heirloom variety which produces heavy crops of red fruits. Unique ferny foliage which performs well in a pot.

Enjoy early May in the Garden!

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