By Dr. Robert Moon
The street trees in your front yard need plant food in the form of fertilizer or plant nutrients to grow healthy and vigorous. A good visual indicator of low vigor and low plant nutrient level is yellowing, chlorotic leaves and this yellowing color can be seen in many trees on Harvest streets.
Many of you might be thinking that your street trees can’t be hungry because you have been fertilizing these trees, but let me tell you the problem. The parkway area between the sidewalk and street is irrigated with drip irrigation (buried lines). Drip irrigation supplies adequate moisture for these trees but since the water is not surface applied, any dry fertilizer on top of the ground will remain there until it rains or has been hand watered into the root zone. If this makes you question the use of drip irrigation in this area, realize that drip irrigation solves the problems of running water down the street and wasting of water. But it does require that you be more vigilant to make sure the fertilizer you are applying gets down to the roots of the tree.
To make sure your trees receive adequate fertilization, you can fertilize with a liquid fertilizer, a granular fertilizer that you water into the soil around the tree or tree spike fertilizer. For these trees, I suggest you use a liquid fertilizer every 6 weeks from February through September. Miracle Gro has a good liquid tree and shrub plant food that is readily available and easy to find. The applicator provided with the fertilizer makes it easy to apply. You can also fertilize the trees every 6 weeks from February through September with the Harvest fertilizer. At each application, apply 2 pounds of fertilizer around each tree spread evenly from the trunk out to the drip line. Make sure to thoroughly hand water in this granular fertilizer after each application. If liquid or granular fertilizer takes more time than you have, you can purchase tree fertilizer spikes from your local garden supplier. Look for Miracle Gro Tree Spikes or Jobe’s Tree Fertilizer Spikes. When applying any of these methods, follow the label directions for tree fertilization.
You also need to know that your shrub beds next to the foundation of your house have drip irrigation. Drip irrigation was installed in these areas to provide moisture to shrubs and to protect your home’s foundation.
Just remember, street trees are worth the extra effort to provide needed nutrients. These trees will provide shade, beauty and extra value to your neighborhood.