News Article for March 10, 2008:
Lawns are beginning to green up, but resist the temptation to fertilize now.
It is still too early to fertilize your lawn. We had at least 3 big frost just this past week and weekend.
Our lawns typically start green up in March, but you should wait until early to mid-April before fertilizing.
It may seem odd to wait but there are good reasons.
First, if you fertilize early you will get lush growth. If you get a freeze or big frost on the lush growth you will damage the lawn. We generally figure the last average freeze dates for our location to be March 20. That date is only 90% accurate, or 10% of the time the last spring freeze is later. (I am not sure that Mother Nature reads those reports.)
Next, even though you may see new green blades, those grass plants are reemerging from energy stored in the crown of the plants. You will have a lot of older roots die off and new roots will replace them in the spring. The grass plants do not have enough developed root system early in the season to utilize the fertilizer that you apply.
Early fertilization also makes your lawn more susceptible to the grass disease brown patch. Brown patch is usually active in the spring and can cause considerable damage and loss of grass in the lawn.
When you do fertilize later in April, you should follow the recommendations from your soil test. If you have had problems with your lawn you should get a soil test prior to fertilizing.
If you are on a maintenance program with your lawn then you can either use a commercial lawn fertilizer that is labeled for your grass specie or you can use a general fertilizer such as 8-8-8. The numbers tell you the percentage of nitrogen, phosphorous and potassium, in that order. If you use 8-8-8, figure your application rate at 6-7 pounds per 1000ft² of lawn area.
You are probably encountering a lot of winter weeds in the lawn now also. The same patience should be applied and you should wait for this chore also.
Your lawn grass is in its most vulnerable state when it is coming out of winter and transitioning to spring growth. Just as stated above, there is limited root system to support the plant. Although you can apply any recommended herbicide to your lawn, most of these herbicides have some negative effect on the grasses also. Grasses generally tolerate the ill effects of herbicides with minimal damage under normal growing circumstances. The transition period that we are in is not normal growing conditions and the added stress of a herbicide treatment now could severely damage your lawn.
Just as with fertilization you should wait until 3 weeks after green up for your herbicide application. This should put your application into April.
For more information on this or related topics, contact Kenny at 225-686-3020.