I have a large area that has largely been taken over with weeds. I have tried to establish lawn here, but the limiting problem seems to be a 2-3" depth of topsoil, with a large amount of clay underneath (the lawn is easily pulled up, even after a couple of years). I have had the soil tested (U. Del.), and have roto-tilled the soil once to kill-off the weeds, and break up some of the clay. That was almost two weeks ago, and I ready to till it again, adding the recommended soil ammendments. My intention is to plant a mix of dutch clover and tall fescue. I am assuming that the beginning of November is too late, because germination probably won't happen. My question is if I can't plant the fescue/clover mix now, what is the best cover crop to plant that I can re-till in the early spring in preparation for re-seeding? Or am I completely off, and there is a better way to re-establish my lawn? I was considering planting dutch clover exclusively, but I was concerned about winter die-off, and a mono-culture turf. We do stay with an almost exclusive organic and manual lawn care to provide a friendly environment for bees, fireflies, and pets. Thanks!
Montgomery County Maryland
Here are some options. You did not mention how large the area is.
If you have bare soil, you can seed annual rye now, however, germination will be iffy. You will have to provide good seed to soil contact for germination. You can use a hard rake if need be. Sow seed and cover with a light layer of straw.
Seed with the mix of fescue and clover in the spring around March.
Or you can lay sod. This can be laid as long as the ground is not frozen. You have to be able to prepare the soil in advance of the sod delivery. The site needs to be prepared for the sod which includes a soil test if not done within the last 3-5 years, rough grading, adding soil amendments and final grading. Select a certified sod produced under the supervision of the Md Dept of Agriculture free from weeds, undesirable grasses, and has fewer insect & disease problems. https://mda.maryland.gov/plants-pests/Documents/MDSODDIRECTORYNOV2017.pdf
See our publication for more information on site preparation steps, sod, and sources. http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG102%20Lawn%20Estab...
If you do not have bare soil, you can wait until March to seed with tall fescue and clover. We do not recommend constantly tilling as it brings up weed seeds, destroys the organic matter, etc. You can core aerate or use a hard rake for good seed to soil contact. Here are recommended cultivars for tall fescue http://extension.umd.edu/sites/extension.umd.edu/files/_docs/programs/hgic/Non_hgic_pubs/TT-77%20Rec...
Planting white clover exclusively would not be a good idea. It grows vigorously in the spring and fall. It does not like the intense heat of summer and may go dormant during drought - in this regard it is similar to cool season turf grasses such as tall fescue. In extreme drought, large patches will likely die. Also, in the winter it goes dormant. So you may have a mud pit and nothing to hold the soil.
Clover is considered a short lived perennial - clover lawns will likely need to be overseeded every 3-4 years. Clover grows best where it receives at least 6-8 hours of sun and will not establish well in shady areas.
Here is information on lawn renovation http://extension.umd.edu/hgic/lawns/lawn-renovation
Oh, I completely forgot the area (and the soil analysis). Yes, calcium is really high.
3 sections of lawn, seperated by concrete. I am only doing 2 this year (long story).
One section is 1,722 sf, pH is 6.6, P is 23, K is 55, Mg is 162, Ca is 214. (Pb is 139 ppm)
One section is 1,024 sf, pH is 7.4, P is 70, K is 103, Mg is 177, Ca is 220. (Pb is 318 ppm)
My concern with winter rye is deer (we basically have domestic herds here!). I was considering a mix of winter wheat and hairy vetch. My intention is to till it in early enough to do the fescue/clover mix in March.
Your first area, with 6.6 pH, looks to be in a good condition for lawn re-establishment. In the second area, the pH of 7.4 is a little higher than ideal but not so high that you would need to apply sulfur or aluminum sulfate. There is still time to plant winter wheat and hairy vetch but do it as soon as you can. We recommend seeding a little heavier (about 25% above the recommended rate) and make sure you tamp down the seeds to get good seed-soil contact. You can do this either by using a roller or just walk over the area after you seed to press the seeds down into the soil. Raking the seeds over is usually not sufficient.
We would be interested to hear how the fescue/clover mix does for you and how you like it. We are trying to encourage more people to get away from the notion of a monoculture lawn, so if you would be willing to report back and share your experience with us, we would be interested in hearing about your results.
Happy to report back, I especially appreciate the advice. What is the best way to report on this so that the right people get the input?
Great! You can report back to us by submitting your comments using this same online system. You can open a new question and share your comments and photos. We'd appreciate it! https://extension.umd.edu/learn/ask-gardening