Gardening with Allen: It’s a good time to reapply fertilizer

I am concerned about the effect of this hot, dry weather on my flowers, vegetables and trees. How should I be watering and fertilizing them?

You have probably been watering your hanging baskets and other containers every day. Baskets in the sun may even need a second watering when the temperature is over 90 degrees. Look for wilting or drooping leaves as an indicator. Whatever fertilizer you applied when they were planted has probably mostly been leached out of the soil. Now is a good time to make another application of fertilizer to your containers. If you have been using liquid fertilizer, you can continue using it on a weekly basis. Even if you applied slow-release, coated fertilizer such as Osmocote, it is probably also mostly used up. I use Osmocote and I always make another application to my containers in July.

I also like to apply more fertilizer to my annual flowers to stimulate new growth. This is particularly true if I notice older leaves turning yellow. If my flowers in or out of containers have grown beyond where I want them, I may give them a trim before I fertilize. Trimming also stimulates new growth and bloom.

Long-lasting vegetables such as sweet corn, tomatoes, squash, pumpkins, peppers and cucumbers also get a second fertilization about now. The quick-maturing vegetables like lettuce, radish and peas don’t need a second application unless you make additional plantings. I use a general purpose fertilizer such as 16-16-16 for my vegetables and flower beds. I’m on a two-day interval for watering flowers and vegetables, but every day when the temperature reaches 90 degrees.

Water trees

Large, mature trees may get enough water if they are growing in lawns or other irrigated parts of your landscape. However, trees will benefit from extra deep watering at least once a month during the summer and fall.

Most sprinklers only wet the soil a few inches deep and tree roots extend 2 feet or deeper in the soil. The highest concentration of water-absorbing tree roots are 2 or 3 feet inside and the same distance outside the outer edge of the branches. Roots near the trunk are mainly large roots for anchoring the tree.

I have found that one of the best methods of concentrating moisture in this drip-line area is with a soaker hose or sprinkler hose. These hoses can be curved around one or more trees and allowed to run for several hours. I often let them run overnight to get the soil wet deeply. You can tell how deep the water is penetrating by making a temporary opening with a shovel. If you have a sprinkler system, you may just want to run it through two or three cycles in the same day. It will not hurt lawns, flowers or shrubs to get an extra deep watering occasionally.

Trees and shrubs growing in or on the edge of the lawn get fertilized with the lawn. Trees and shrubs in other locations just need once-a-year fertilization, usually in the early spring.

Water trees

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