For people who have warm season lawns such as buffalo grass, zoysia or Bermuda, there is less maintenance, especially at the first of the year. Warm season grasses have now come out of dormancy, and adding a little fertilizer now will help the turf have better growth and a deeper color. I found an article from Ward Upham, K-State Research and Extension’s horticulture expert, to give you some tips on how to help your warm season lawn look its best this summer.
June is the time to fertilize warm-season lawn grasses such as Bermuda grass, buffalo grass, and zoysia grass. These species all thrive in warmer summer weather, so this is the time they respond best to fertilization. The most important nutrient is nitrogen (N), and these three species need it in varying amounts.
Bermuda grass requires the most nitrogen. High-quality Bermuda stands need about 4 lbs. nitrogen per 1,000 sq. ft. during the season (low maintenance areas can get by on 2 lbs.). Apply this as four separate applications, about 4 weeks apart, of 1 lb. N per 1,000 sq. ft. starting in early May. It is already too late for the May application, but the June application is just around the corner. The nitrogen can come from either a quick- or slow-release source. So any lawn fertilizer will work. Plan the last application for no later than Aug. 15. This helps ensure the Bermuda grass is not overstimulated, making it susceptible to winter-kill.
Zoysia grass grows more slowly than Bermuda grass and is prone to develop thatch. Consequently, it does not need as much nitrogen. In fact, too much is worse than too little. One and one-half to 2 pounds N per 1,000 sq. ft. during the season is sufficient. Split the total in two and apply once in early June and again around mid-July. Slow-release nitrogen is preferable but quick-release is acceptable. Slow-release nitrogen is sometimes listed as “slowly available” or “water insoluble.”
Buffalo grass requires the least nitrogen of all lawn species commonly grown in Kansas. It will survive and persist with no supplemental nitrogen, but giving it 1 lb. N per 1,000 sq. ft. will improve color and density. This application should be made in early June. For a little darker color, fertilize it as described for zoysia grass in the previous paragraph, but do not apply more than a total of 2 lb. N per 1,000 sq. ft. in one season. Buffalo grass tends to get weedy when given too much nitrogen. As with zoysia, slow-release nitrogen is preferable, but fast-release is also OK. As for all turf grasses, phosphorus and potassium are best applied according to soil test results because many soils already have adequate amounts of these nutrients for turf grass growth. If you need to apply phosphorus or potassium, it is best to core aerate beforehand to ensure the nutrients reach the roots.

Alicia Boor is the Agriculture and Natural Resources agent for Barton County K-State Research and Extension. Contact her by email at aboor@ksu.edu or call 620-793-1910.