Monthly Archives: June 2015

Balcony Gardening – Succulent Gardens

The Summer Solstice is past, Fourth of July is coming up. What if you forgot to water the flowers, the vegetable plants did not get enough sun and then it hailed!

Denver Botanic Gardens - Succulent Garden

Denver Botanic Gardens – Succulent Garden

There is a succulent garden for all budgets and all spaces:

–  buy individual cactus and arrange the pots on a tray a quick solution and many can become house plants at summer’s end.

– many garden centers have succulent gardens ready for purchase, ask how to care for them

–  buy annual or perennial rock garden plants and create your own using a shallow container, cactus type potting soil and gravel

– Winter-hardy cactus could be an option for your balcony

Plant Select Petites  has “Garden Treasures for Small Spaces” and a lot of suggestions for plants, planting and maintenance.

Pay attention to where you buy your plants.  If they were indoors they will do best  in a shady location.  If they were outside in full sun they will enjoy a sunny balcony.

If a cactus or succulent looked sunburned that is very possible if it was too much sun too soon.  Put your succulent garden in a part sun, part shade location to begin.  Even a cactus can get sunburned.       

 When in doubt – don’t water.  Too much water will cause the roots to rot and the damage is hard to spot until it is too late.  (I’ve had succulents surprise me by just falling over!)

The internet has lots of information on succulent gardens.  If all this sounds like a better project for next month, then a few pots of red, white and blue petunias is a cheerful alternative.  Enjoy!

This is Pollinator Week!

Natl pollinator week logo

Photo used by permission.

Did you know that this week is Pollinator Week?  According to the non-profit Pollinator Partnership, since Pollinator Week’s inception in 2007, the event has grown exponentially in scope.  Last year, Secretary of Agriculture Tom Vilsack, U.S. Secretary of the Interior Sally Jewell, and 45 governors designated Pollinator Week as a week to celebrate and protect the nation’s pollinating animals.Pollinators are the creatures which assist about ¾ of all flowering plant species to move pollen from plant to plant for fertilization and creation of new seeds.  About 200,000 species of pollinators are insects such as flies, beetles, wasps, ants, butterflies, moths, and bees. About 1,000 of all pollinators are vertebrates such as birds, bats, and small mammals.

Pollinators are critical to an ecosystem. They ensure full harvests of crops and contribute to healthy plants everywhere.  “One bite out of every three” is delivered by pollinators, and, in the U.S., about $20 billion worth of products are produced by pollination each year.  Wildlife is also dependent on pollinators for plants, fruits, and nuts, which provide direct food sources and essential cover for protection.

How we can help the pollinators:  The US Botanic Garden and the North American Pollinator Protection Campaign (NAPPC) collaborated in 2004 to produce “The Great Pollination Partnership”.  Following  are some of their suggestions for gardeners:

Use a wide variety of plants that bloom from early spring into late fall. Put plants attractive to pollinators in clumps, rather than as single specimens. Include native plants adapted to your local climate, soil and insects. Night-blooming flowers are important to support moths and bats.

Avoid modern hybrid flowers, especially those with “doubled” flowers in which often the pollen, nectar and fragrance may have been bred out in efforts to create “perfect blooms”.

Reduce or eliminate pesticides whenever possible. If you must use a pesticide, use the ones least-toxic to pollinators as possible.  Read labels carefully and spray at night when bees and other pollinators are not active.

Include larval host plants in your landscape. If you want colorful butterflies, you must have caterpillars first!  The caterpillars WILL eat these plants, so put them where unsightly leaf damage and possible weedy nature can be tolerated (hello, milkweed). A butterfly guide will help you determine the host plants you should include.

Don’t cut down that dead limb!  A dead tree or an occasional dead limb will provide nesting sites for native bees. You can build a “bee condo” by drilling holes of varying diameter about 3 to 5 inches deep in a piece of scrap lumber mounted to a post or under eaves with southern exposure.  Make sure these are not a safety hazard for people walking below by putting them higher than six feet from the ground.

Add to nectar resources by providing a hummingbird feeder. To make artificial nectar, use 4 parts water to 1 part table sugar. Never use artificial sweeteners, honey or fruit juices. Place something red on the feeder. Clean your feeder with hot soapy water at least twice a week. Butterflies need resources other than nectar and are attracted to unsavory (read “rotting”) foodstuffs. Try putting out slices of overripe bananas, oranges and other fruits, or a sponge in a dish of lightly salted water.

Learn more about pollinators. Get some guidebooks and learn to recognize the pollinators in your neighborhood. An excellent source for pollinators and the plants which attract them by region (selected by entering your zip code) is found at  (select “planting guides”).   Denver zip codes fall within the “Great Plains-Palouse Dry Steppe Province” for which the guide is not yet available.  Other regional guides including parts of Colorado are available, and would serve as helpful guides until our own regional guide is published.

Hopefully, these ideas from the Pollinator Partnership and the North American Pollinator Protection Campaign will assist you in making your garden more pollinator-friendly.  Do so, and we all benefit.

by Mary Beth Cooper, Denver County Master Gardener

One Less Ash Tree for Emerald Ash Borers

yellow tree leaves
When I planted a white ash tree about 10 years ago, I never dreamed I’d be chopping it down while it was still healthy. But I did just that earlier this season and took the loppers to the tree while it was sending out new leaves.

I decided to take action now instead of waiting for the Emerald Ash Borer (EAB) to take it out one day in the future.

It wasn’t an easy decision. I liked this tree a lot, especially in the fall when the leaves turned a brilliant yellow. But it’s only a matter of time before the dreaded EAB makes its way into my landscape and forces my hand.

The tiny Emerald Ash Borer has already caused the death or decline of tens of millions of ash trees in at least 20 states and now it’s in Colorado.

I chose to remove the tree this season to avoid my limited options in the future. Like other ash-tree owners, I’d have to decide whether to budget for the expense of treating a taller tree with insecticides every one or two years to prevent EAB damage or wait for the borers to kill the tree slowly and then hire someone to remove it for me.

Now that this ash tree is gone, I can take my time and find another kind of tree to replace it.

Then I’ll be able to focus my preventive efforts on the much larger ash that shades most of the front yard. That tree is more valuable and will be worth the cost of treating it, once the time comes.

Right now, home owners and urban foresters in and around Boulder are trying to make the same kinds of decisions. They’re deciding whether to treat their trees with insecticides — while weighing the costs with the environmental hazards; measuring the effectiveness with ease of application.

If you have ash trees on your property, you’ll have to make similar decisions in the future, too. Now’s a good time to start thinking of what you’ll do once the EAB invades your landscape. Would you remove a healthy ash tree as a drastic measure to prevent EAB in the future?

There are some good resources to help you decide, including CSU’s Department of Bioagricultural Sciences and Pest Management website and the Colorado Department of Agriculture EAB website that includes an Ash Tree Zone interactive map and a way to sign up for the EAB newsletter to stay informed.

By Jodi Torpey
A Denver master gardener

Decoding Fertilizer Labels

On a recent visit to a garden center, a customer was overhead asking  about the prominent numbers on the front of the fertilizer package. What  does  13-25-12 mean?

The numbers correspond to the percentages of three different compounds: Nitrogen, Phosphorous and Potash (or Potassium). Each can contribute to plant health. Nitrogen, along with other nutrients, helps plant foliage grow strong. It is used in large amounts by plants. Ever notice your lawn has a growth spurt after fertilizing? That’s likely Nitrogen at work. High Nitrogen fertilizers  make for quick growth but weaker plants, which can more easily succumb to pests and diseases

Phosphorous helps plants develop strong roots and abundant flowers and is very beneficial to sandy soils, which are common in Colorado. Phosphorous does not leach out of our soil, so continual additions are not needed in the landscape.

Potash aides in overall plant health. Front Range soils have ample potash, so it is not advised to add more in our soils. It won’t help either your garden or your wallet.

So which is best?   There is no one-size-fits-all answer, but in general:

  • Lush, flowering garden pots benefit from weekly feeding of water-soluble fertilizer high in phosphorous.
  •  Houseplants can benefit from fertilizers with equal numbers of each nutrient.
  •  In the garden, it is best to get your soil tested. Information can be found at: This will greatly help you add the correct nutrients for your soil and growing needs.

A word of caution: More is not better. Always follow the application instructions and give the plant time to absorb the nourishment.

Lots more information on fertilizers and soil amendments can be found at: