For:
By: Daniel E. Mullins
Extension Horticulture Agent
Fertilizing Too Early is Risky, Wasteful and Environmentally Unfriendly
I do my best to stay out of a gardening information mode when not at work. However, sometimes during normal off duty activities something is seen that draws special attention.
So it was last week-end. While visiting a local store, I saw people loading up on lawn fertilizer, while some were buying a fertilizer that also contained a weed killer. I thought “surely not” yet, in hopes that these gardeners were only stocking up for spring.
It was a beautiful day, so that afternoon I found myself driving through two residential areas. Unfortunately, some home owners were seen applying lawn fertilizer.
The
third week of February is too early for fertilizing in north
There is also a good chance that fertilizing too early can indirectly damage the lawn. Making nitrogen available too early can cause the grass to green up prematurely with the first warm spell, only to be killed by a spring freeze.
Excessively early fertilizer applications are not environmentally sound. The soluble elements in most lawn fertilizers such as nitrogen and potassium are subject to leaching if not used by the grass. Little can be used by lawn grass this month, because of inactivity.
Soils
remain cold at this time of year and the roots of the warm season grasses and
other plants are functioning very little.
Last Monday during mid-day, the soil temperature in central
Instead of trying to jump start spring, let your lawn tell you when to fertilize. Wait until there is a uniform green up and some growth. This is the first time of the year that the grass can take up and use the fertilizer.
Pre-emergent lawn herbicides are sold alone and in combination with fertilizer. These products can help to prevent spring weeds but only work well when applied at the right time.
In order to work best, a pre-emergent weed control product must be applied just prior to the time that spring weeds are expected to begin germinating. Under good conditions they can then provide up to eight weeks of control. If applied too early, part of the effectiveness is lost and if applied too late there might be a lack of control because the weeds are too mature.
The best time to apply a pre-emergent product in the spring can vary by a few weeks, depending upon temperature. When planning to prevent crabgrass and other typical weeds watch the dogwoods and azaleas. When these two plant species bloom, crabgrass is beginning to germinate. In general this time is about the first of March, but these two indicator plants are usually better than the calendar for determining a time to apply a pre-emergent weed killer.
Note: Use dogwoods and azaleas as indicator plants only. Do not use pre-emergent herbicides within the root zone of these plants, as some can cause serious damage.
Question of the Week: I plan to grow indeterminate type tomato varieties in cages this year. How can I best prune to keep them from growing above the cages.
Answer: The growth habit of
the indeterminate varieties is such that they grow and bear over a longer
period of time. Do not prune the ends of
the vines as this will cause the plants to revert to juvenile growth and might
shorten your harvest season. Allow the
vines to grow up, then down and around the cage, tying them to prevent contact
with the ground.