Monday, January 25, 2010
Tips: Soil Temps & Weed Control
Soil Temps at 2 inches on Jan. 25 ranged from 55 degrees F near the MS Gulf Coast to about 45 in the far northern part of the MS delta. What a change from frozen soil in the 1st week of Jan! While there are debates about proper times to apply preemergance weed control for crabgrass, most agree that the millioins of seeds in the soil will start to germinate when soil temps approach 60 degrees. Vegetable gardeners using one of the trifluralin products for weed control should be aware of local soil temps. Check temp by sticking a thermometer in the ground at the depth you are going to plant. Another way is to consult the SCAN program at http://www.wcc.nrcs.usda.gov/scan/Mississippi/mississippi.html This is a federal network of weather stations (several of which are in MS). Click the dot closest to you and look at the C1TMP column. This gives you the soil temp at 2 inches in centigrade. (FYI: it's easy to remember 10C is 50F and 21C is 70F). These are important in relation to plant growth. Few things grow well below 10C and most everything grows well above 21C.