October 7, 2009
After talking to a few people this week, there seems to be some confusion about fertilizing plants in the fall. Let me take a few moments to explain to you about fertilizing plants at this time of the year.
Let’s start with lawns. Fall is one of the most important times of the year to fertilize your lawn. An application of a fall type of fertilizer will strengthen the roots of your lawn and cause those roots to dramatically expand out into the soil. The expanded root system will produce many new blades of grass in the spring. This will result in a thicker lawn that will help to force out weeds and give you that lush lawn you have been looking for.
Your perennial beds will benefit from an application of superphosphate at this time of the year. Superphosphate is high in phosphorous. Phosphorous will stimulate root growth at this time of the year. This will make for a much stronger plant in the spring. The phosphorous will also promote flower bud production next year. More flower buds equals more flowers. After all, getting more flowers is what its all about when it comes to perennials. One of the good things about using superphosphate is that it does not contain any nitrogen. If you apply nitrogen at this time of the year, you may create new green growth that won’t harden off before the cold weather sets in for the winter.
Trees and shrubs should not be fertilized until they go dormant in the fall. The lowering of the temperatures causes a plant going into dormancy. Generally speaking, a frost may be enough to put plants into dormancy. In the case of perennials, a frost may kill off the top growth of the plants and put them part way into dormancy. However, if the temperature rises again, the plant may try to put out new growth. It is the soil temperature that causes the plants to truly go dormant. This usually occurs after the plants have been exposed to several frosts. On average, this happens around here around the end of October. Deciduous trees and shrubs will drop their leaves. Evergreens will usually turn a darker color. Once this happens, you can fertilize the plants with an organic fertilizer. This fertilizer will help to strengthen the root system. If you go south for the winter and you leave before the plants go dormant, you can apply superphosphate around the base of the plants. This will help to develop the root system without the stimulation of green growth that would happen by applying other types of fertilizer and having the temperatures rise again.
We have been lucky to receive rainfall over the past weekend. The soil had become dry and many plants were having a hard time getting the water they desperately need in the fall. Many of your trees and shrubs need to take up extra water in the fall to allow them to store water for the winter. This stored water is drawn out of the plant by the dry winter winds. If the plants don’t get a good soaking rain each week, you will have to supply that water. Keep an eye on the weather and if there is no rain in the forecast, you will have to be watering your trees and shrubs.
Well, that’s all for this week. I’ll talk to you again next week.