Gardening: Improve plants, trees in your landscape

Annuals offer a good variety of colors.  All perennials have a flowering period.  For almost all of them, it will come over a period of two or three weeks.

Annuals offer a good variety of colors. All perennials have a flowering period. For almost all of them, it will come over a period of two or three weeks.

Special on the Star Telegram

Some questions defy answers. “How big is the universe?” “Why was it so difficult for me to find a date?”

And there are some in horticulture that are just as difficult for inquiring minds to process. These will be the focus of our words today as I try to give them answers as I fly by.

What is the best fast growing shade tree?

“Fast growth” and “quality shade trees” are mutually exclusive. All fast growing trees have at least one fatal flaw. They all have weak wood, and that makes them prone to a variety of insect and disease problems. All have a short life expectancy. However, to give you an answer, if I had to choose a fast growing shade tree for my own landscape, it would probably be a fruitless mulberry. For those of you who are moaning now, this just proves my case.

How often should i water my plants?

I have an answer for you, but I’ll save it for a moment. Several facts will determine your own precise answer. These include the types of plants, their growth rates, the types of soil, solar radiation, wind speed and temperature. But the real answer to the question is that the frequency will vary widely. You need to learn to determine when it is time to water. Learn to recognize the symptoms of drought. Let your plants tell you when they need water. Some will wither. Others change color. Others may not have any visible signs at all. You have to learn to feel the ground.

Why did my plant die when neighbors on both sides of me have the same plants and theirs is fine?

This one is just too open. You have to train yourself not to look at the neighbors’ plants! Your soil can be different. Exposure to sunlight and reflected heat may not be the same as yours. They may have watered a little differently or fertilized their plants a little better. All you can do is take the best possible care of your plants and hope they are good for you.

Which perennial can I plant for years? I’m tired of having to replant annual plants every year.

To answer that question, I need to adjust people’s view of perennials. All perennials have a flowering period. For almost all of them, it will come over a period of two or three weeks. Outside of this time, they won’t be particularly attractive. For the perennial gardener, it is imperative to have 15 or 20 types of plants for a sequence of flowers. The truth is, perennial gardens are as much, or more, work than gardens with annual flowers.

What’s wrong with my St. Augustine? It looks awful. I think it’s dying.

This is a difficult matter. This time of year, in the heat of summer, St. Augustine is most often plagued by chinch bugs and gray leaf spots. Chinch bugs make the grass appear dry in hot, sunny areas. However, watering does not help. Upon closer inspection, the BB-sized black insects become visible. Several readily available insecticides can be used to control them.

A gray leaf spot causes the grass to develop a yellowish hue as a whole. A close examination of the blades reveals small, diamond-shaped lesions. This fungus is aggravated by the application of nitrogen in the summer. Control it with daconil or azoxystrobin fungicides and do not apply fertilizer between mid-June and early September.

How long does it take before I can plant new rose bushes where the rose rosette virus has killed the old ones?

The virus does not persist in the soil. In theory, you could transplant almost immediately. However, there is a good chance that other rose plants in your neighborhood are also infected. If so, the microscopic mites that originally brought the disease to your plants could bring them back directly to your new plants. As long as you transplant with the knowledge that your new plants may not last indefinitely, and if you carefully select plants when purchasing that are not infected at the time of purchase, you can give it a try. However, many of us limit the number of roses we plant until some of the secrets are cleared up.

Why do people insist on topping their crepe myrtle? Haven’t you heard that it ruins the natural shape of the plants and does nothing to help them bloom better?

I have to admit that I added this question for my own pleasure. Like a pastor trying to show us how to become better people, I’ve spent a career teaching how not to prune crepe myrtle. “Topping” is at the top of this list! I feel like progress has been made, but it seems like it will take me about five more careers to get the job done. In fact, that’s a truthful statement. Topping ruins crepe myrtle.

You can hear Neil Sperry on KLIF 570AM until 1:00 p.m. on Saturday afternoons and on WBAP 820AM on Sunday mornings 8:00 a.m. to 10:00 a.m. Join him at and follow him on Facebook.

Related stories from Fort Worth Star Telegram

Comments are closed.