By Calvin R. Finch, PhD, SAWS Conservation Director, and Horticulturist
Week of September 19, 2005 

“Lawn Chores for the Autumn”

            It is time for some important lawn activities.

              Sandburs are maturing and soon your pets and you will have the pesky burs stick to paws and pant legs.  The best way to prevent sand burs is to apply pre-emergent herbicide in April and June and/or to apply an MSMA herbicide to young plants over the summer.  See plantanswers.com for the recommended prevention strategy. 

            If you have the plants now with maturing burs, the plants can still be pulled out by hand if there are only a few.  Wear leather gloves.  Throw the plants, burs and all, into the garbage.  It also reduces bur problems if you mow them low as soon as heads appear.  The burs are still on the ground, but are not as likely to attach your pant legs when they are cut down.   

If you want to prevent winter weeds it is time to apply the pre-emergent herbicide.  Herbicides like Amaze, XL, Balan and Betasan will prevent many of the annual winter weeds from germinating.  In many yards bedstraw, rescue grass, henbit, annual bluegrass, dandelion, and tickseed are a problem. The herbicide label will tell which weeds the product will prevent.  Select the product that suits your weed problem. The granular materials need to be applied and activated at the soil surface before the first cold wave stimulates the weed seeds to sprout.  Follow the instructions closely.

            October 1 is the target date for “winterizer” fertilizer.  There are many brands and all have some variation of the term “winterizer” on the label.  Common formulas are 15-5-10, 18-6-12 and other 3-1-2 ratios.  The grass plant stores the nutrients for cold resistance and a fast green-up next spring.

            Autumn is brown patch fungus time.  The disease develops when the nighttime temperatures moderate.  The best way to reduce brown patch infection is to reduce watering in the fall beginning in September.  The disease always seems to start in the lowest, wettest part of the lawn.  A lawn that is on the dry side rarely develops brown patch.  It also helps to prevent the disease if, when you do water, it is in the morning rather than the evening.  Several fungicides including Turfcide and Fungaway will stop the spread of brown patch.

            Although you can lay sod all year if you purchase the material from a reliable supplier, September is the last month when it is reasonable to try and create a lawn with seed.  The seed requires warm weather and water to germinate and then requires a period of warm weather to produce a sod complete with a root system.  Apply 2 – 3 lbs., of Bermuda grass seed per 1,000 sq. feet to a tilled and leveled seed bed.  If you are able to incorporate 2 – 3 inches of compost and 2 lbs., of winterizer fertilizer (per 1,000 sq. ft.) to the seedbed, it will really make a difference in growth rate and water use.  The $25/cu. yd., of compost you pay and spread will be repaid by reduced need for watering the first summer.  One cubic yard of compost applied at two inches deep will cover 162 sq. ft., of lawn (6 cu. yds./1,000 sq. ft). 

            Bermuda grass and buffalo grass will only prosper in full sun.  For a shady lawn, use zoysia or St. Augustine grass.  For a copy of the SAWS three-week watering plan for starting a new lawn call (210) 233-3649.  Remember, all types of lawn grass require at least four inches of soil, 6 inches is better.