Let’s take a look at spring weeds: clover and dandelions. It can’t be overstated enough to work in the Spring and Fall to establish dense and healthy turf. Our Organic Turf Care Calendar breaks down this importance in April-May. A thick stand of turf grass will crowd out annual weeds.
We want you to know what weeds you’re looking at and why they’re there.
Clover is a cool-season perennial and is more likely to establish itself during a cool, wet spring before the turf grass starts growing. Some consider clover to be a weed. However, clover can be a beneficial plant because of its ability to obtain nitrogen from the atmosphere and ‘fix’ it in nodules on its roots. Clover will germinate in soil temperatures as low as 45° while cool season grass seed prefers soil temperatures in the 60° – 65° range. It does well when there is not a lot of nitrogen available in the soil. Additionally, when turf grass is thin, light can reach the soil surface and encourage the clover to germinate. Because clover seeds have a hard coat they can survive in the soil for long periods of time until conditions are right to encourage their germination. The presence of large areas of clover in a lawn or athletic field indicates the area is not receiving adequate fertilization.
Dandelions can be difficult to control since their seeds travel via the wind. However, dense grass prevents the dandelion seed from finding its way to the soil. To eliminate areas where dandelion seeds can get a foothold, thin areas of your lawn should be regularly over-seeded. Dandelions also like soils that are slightly acidic and low in calcium. Large dandelion rosettes are an easy indicator of low levels of calcium in the soil. It is important to have your soil in the proper pH range (6.5–6.8). Use a calcitic lime to improve calcium levels while raising pH to favor the growth of grass. If possible, grass clippings should be bagged when dandelions are in flower to prevent spreading the seeds.
Stay tuned for our blog next week, when we look at spring weeds chickweed and plantain.