Why does Weed'n'Feed granular turn my lawn black on application?
Weed and feed states that buffalo will turn black on application but return to normal, how long does this take
Hi Marie,
The active ingredients in the Weed n Feed Granular are sulphate of iron and sulphate of ammonia. When applied to a moist lawn area in which there are weeds and left for 2 days, the iron has a salt burn effect so that the flat weeds receive a relatively severe burn compared to the vertical blades of grass.
After 2 days of having the product on the leaf blade you will notice a black tinge to the grass. After a thorough watering you will find the grass will green up again in about 5 days. Hopefully it will rain, which will certainly help to green up the grass in a shorter period of time.
yates
Answered: 6 Dec, 2011