Gladiolus fare well in valley

: A friend asked me to find out why her wisteria plant has not bloomed since she purchased it. The leaves are green and the sun hits it in the morning. What kind of food or fertilizer does it need and how often does she need to fertilize it?

A: The primary reasons for not blooming are immaturity of the plant, not enough sun or winter freezing damage to the flower buds. Typically, it will take wisteria about four years to bloom. It will take longer than that if you fertilize it too often or prune it too much. If it is not getting enough light (5 to 6 hours), it may never bloom.

Trellis these plants for best blooming results and easier maintenance. Take a look at this information from Ohio State University. http://ohioline.osu.edu/hyg-fact/1000/1246.html.

I do not think Southern Nevada’s cold temperatures are a problem unless the cold comes very late in the season when the flower buds are beginning to form.

The plant should be getting full morning sun but some relief from direct afternoon sunlight and high temperatures. Being located near a hot west or south wall is probably going to be a problem for this plant. An east-facing wall would be better. Try to keep it in a location protected from wind.

I would fertilize it once only in the spring each year, about now, and do nothing after that until the plant begins to bloom.

I would minimize pruning to just training it on a trellis of some sort. There should be no unnecessary pruning until you see blooms beginning. After that, you can prune more heavily.

Q: Can I plant gladiolus here? I know bulbs are sold here; they need plenty of sun and are grown in Africa.

A: Glads can be grown here and they do very well. Plant the bulbs or corms in the latter part of March or early April.

First, Prepare the soil well and make sure that it drains freely. Mix our desert soil with about 50 percent compost. Plant the bulbs close together (2 to 6 inches apart) and about 2 to 6 inches deep, depending on the size of the corm. The bottom of the corm is flat and will have a few roots showing. Use a bulb fertilizer or any fertilizer that you would use for other flowering plants.

Glads require even moisture throughout the growing and flowering season. Staking is usually required with the larger varieties to improve the quality for cut flower arrangements.

You will find that the corms have multiplied during the growing season. These smaller corms can be broken off and replanted. It will take two to three years for the smaller corms to reach a mature size that will produce flowers.

Q: I was surprised by one thing in your article in the Las Vegas Review-Journal recently. In describing how to move a plant, you said to “add water as soil is added to hole … will remove air pockets.” Then you state “Do not step on the soil amendment surrounding the plant.” I have always stepped on the soil surrounding any plant I ever planted, from shrubs to flowers. I also have seen landscapers step on dirt to pack it down. So please tell me again, are you never to step on soil around a newly planted plant?

A: Although you will not likely kill the plant, stepping on wet soil surrounding newly planted roots does run the risk of damaging the roots. It also compacts the soil around the roots, minimizing the air content they need for respiration. I have even seen one of our local horticulturists do this when planting and it leaves me wide-eyed. I have done it earlier in my career but no longer do it. It is a matter of learning to respect the plant and its living environment.

Running water in the hole while adding the backfill soil will usually be all that is necessary to settle the soil around the roots and eliminate air pockets, provided the backfill has been amended properly. If done right, you will not need to stake most plants planted from containers.

Q: This past winter I had my front lawn converted to desert landscape. The landscaper placed the stone right up against the plants and trees. It will be a challenge to move the stone every time I have to fertilize. It took me quite some time to do my rose bushes by moving all the stone away from the plants and then mixing granules in with the soil.

When should I fertilize these new plantings and how can I do that without moving all that stone away to feed them?

A: You do not have to move the stone to fertilize your plants. Get some fertilizer stakes and place them under the drip emitters. That is the easiest way. Water from the emitters will move the fertilizer into the plants’ root zones. I would do that now even though they were planted last winter. It is hard to say whether any fertilizer was used at the time of planting.

You can sprinkle granular fertilizers around the plant (not too close to the trunk) and water them in with a hose. Make sure you sprinkle them near the drip emitters or they may never get watered in properly.

You also can add a fertilizer injector to your drip system and fertilize that way.

The last way is to spray the leaves of the plants with a liquid fertilizer solution like Miracle-Gro or Peters.

You should fertilize plants now if using the type that is applied to the soil. If fertilizer is to be applied to the leaves, spray them at the first sign of new growth this spring. If spraying with a liquid fertilizer, use a wetting agent mixed with the fertilizer solution.

Bob Morris is an associate professor with the University of Nevada Cooperative Extension. Direct gardening questions to the master gardener hot line at 257-5555 or contact Morris by e-mail at extremehort@aol.com.