Nutgrass is a rapidly growing, fast spreading grass-like weed from the sedge family. It has flat tapered leaves that are slightly corrugated. It can be prevalent here in tropics all year round, maybe even more so during the warmer months of the year from September to March.
Nutgrass is strong in structure with an extensive root system. Its name comes from the nut-like tubers found on the roots. The tubers act as an energy storage and it can wickedly reproduce over 100 of these tubers in just three months if left unchecked. Further to this, it is possible that it can lay dormant or inactive in soil for many years, which explains why you can have an onset of it when you stir up a part of your yard or after moving into a new housing estate. Dormant nutgrass loves new turf as it is being watered well during the establishment period and can easily push up between the small gaps in the pieces.
It is a problematic weed to pull out. If you can, act quickly to dig it out with a small spade making sure to remove all the roots and bulbs. If any is left behind, it will reappear and become increasingly difficult to remove.
Unfortunately, broad leaf weed killers, like Roundup will not work. The answer is Sempra. Sempra is a water dispersible granule formulation. It is a selective herbicide, made to specifically kill Nutgrass and Mullumbimby Couch (another sedge weed) meaning it won’t kill your turf or plants.
Nutgrass is a tough weed to crack, just like a single session of hand weeding may not end the problem, the same is true for one application of herbicide use. It may take several treatments of the same weeds a few weeks apart to be finally rid of it.
Make sure to read the safety data sheet and follow the manufacturer’s instructions before use. It is best to apply the herbicide during a dry period. Ideally a couple of days after watering. Do not spray if rain is likely, particularly before a downpour or if it’s just before your next sprinkler day as watering will reduce its effectiveness. Never spray on a windy day.
NUTGRASS - Cyperus rotundus
Write something about yourself. No need to be fancy, just an overview.