Garden Don'ts, Part 1

Garden Don'ts - Part I

I was recently asked by a novice gardener to give him a few tips for his garden. "What can I do to grow plants better or have a better looking landscape?" As I sit here and ponder my answer, I think it might have been easier to tell him (and others) what not to do first.

Some of the garden don'ts that instantly came to my mind were:

• Don't work the soil when it is wet. This is not only muddy and messy, it also destroys the soil structure which can ultimately affect soil drainage and plant growth. This doesn't mean you have to wait until the soil is "bone dry" before tilling. The garden is ready to till when a handful of soil formed into a ball crumbles when pressed with the thumb.
• Don't overwater. This one is tricky because sometimes it can be hard to know when a plant needs water and when it doesn't. So - always check the soil first. Poke it, dig around in it a little bit, and lift the container to see how heavy it is - whatever it takes! When the top of the soil is dry, water well - otherwise wait.
• Don't fertilize out of a problem. Many people seem to think that when plants are not growing as expected that they must need an application of fertilizer. Rarely is this the case. If a plant is growing poorly it often means there is a problem in its environment (i.e. not enough sun, pest problems, etc.). Therefore, find out what the problem is first, and then fix it (Fig. 1). Fertilizing only encourages more growth that will have to survive in this difficult environment (i.e. a quick way to set up a plant to fail). Fertilizer only works when poor growth is due to a lack of nutrients (usually nitrogen).

Figure 1.

As I was thinking about this article, I decided to ask my colleagues about a few of their garden don'ts. Boy, talk about opening a can of worms! They had so many garden don'ts that this article will have to run in at least two parts. Check out a few of their suggestions on the next page.

Jeff Iles, chair of the Department of Horticulture and woody plant guru, suggested several garden don'ts for trees.

• Don't plant a tree too deeply. Trees are not like tomatoes - they cannot tolerate being planted deeply. Where the roots flare from the trunk should be planted level with the soil surface or higher in heavy clay soils (Fig. 2).
• Don't buy and plant a tree without knowing its mature size. Nothing is worse than dealing with an "overgrown" tree. It's not the trees fault that it's crowding other trees and shrubs in the backyard or looming menacingly over the house or garage. Give them plenty of room or select a tree that will mature to the appropriate size for your landscape situation.
• Don't severely prune newly installed trees. I know you want to get the lawn mower under the tree - but instead of "limbing it up" in one year, do it over 5 or more years. The leaves on the tree's limb produce food for the growing tree. Severe pruning will actually slow the tree's growth.
• Don't neglect newly planted trees. After planting, watering will be necessary during dry periods for one or two years. It will take a tree a couple of years to establish an extensive root system. This does not mean watering every day or even every week - refer to overwatering tip above.
• Don't be cheap. Remember the old adage "You get what you pay for." This adage also applies to trees. Select a good quality tree that is large enough to easily maintain and hard to forget. You are less likely to neglect a tree that costs $100 than one that costs $10.
• Don't expect mighty oaks in a growing season. Good trees are like fine wines - they take time before they can be fully appreciated. Your children and grandchildren will be the main beneficiaries of your planting efforts. Consider those fast growing and weak wooded trees as firewood for your retirement.
• Don't leave the next homeowner one of your mistakes. One day you too may be on the receiving end of this one! Enough said.

Figure 2. Aspen trees that died after being planted too deeply. Notice the original planting depth is several inches above the root flare."

See also Garden Don'ts, Part II .

This article originally appeared in the 3/9/2005 issue.