Soil testing: It’s a great time to do soil testing now for the vegetable garden as well as perennial and annual beds, turf areas, and areas where you grow fruit. If you haven’t already tilled, you can go ahead and take samples to send to the UW Soils Lab. If you already tilled, this tends to mix the soil layers and the resulting test is less accurate. The main UW Soil Lab facility is located in Marshfield, you can call them at 715-387-2523 for a soil bag and instructions, or pick up bags and directions at the Dane County UW-Extension office on Fen Oak Drive in Madison. You’ll need to send the bag to Marshfield for the test.
Soil testing is important for new gardens so that you have base-line information for fertilizer application, as well as for beds that haven’t been tested for a while. The lab’s standard soil test costs $15 and the report includes information on your soil pH, (this is a measure of the acidity and alkalinity of your soil) percent organic matter, phosphorus and potassium levels and also includes a lime or sulfur recommendation, fertilizer recommendations and other tips. Go to http://uwlab.soils.wisc.edu/ or call the number above for information on how to collect samples and the address to send them for analysis.
Perennials: Divide summer and fall-blooming perennials such as asters, Shasta daisies, daylilies, garden phlox and hostas now before they get too large. Divide sedums as soon as possible after emergence as they are brittle and stems can break during the procedure. You can also divide ornamental grasses once the new growth reaches about 4-6 inches tall (hopefully, you have already removed last year’s old growth). Watch out for late-emerging perennials such as Japanese painted ferns and balloon flowers so you don’t accidentally crush them while dividing the other plants. Don’t give up on your herbaceous hibiscus yet if they are not up; they usually come out around late May.
Jumping worms, mulch, compost and sharing plants: The Wisconsin Department of Natural Resources has a new brochure on jumping worms on its website that gives recommendations on best practices for sharing plants, mulch and compost. Search for "jumping worms" and "WI DNR" and you should find it. Be aware that jumping worms can be present in compost or mulch as well as in soil around the roots of shared plants. Do check your soil for the characteristic "coffee grounds" appearance that indicates the activity of jumping worms before sharing any plants from your garden. Do not share any plants if you see this soil signature. This time of year, the worms have not hatched yet in most areas and are still in their winter cocoons, which are very tiny. If purchasing mulch or compost, it is recommended that you ask how the materials are handled and stored. Larger vendors of compost or mulch licensed by the DNR should be following DNR’s NR 502.12 rule for handling these products. Under this rule, the compost piles are required to hold a temperature of 131 degrees for 15 days and the windrows/piles must be turned five times to ensure even distribution of temperatures. To learn more, see the DNR page on Composting Rules and Regulations. These are some links you may find helpful: http://dnr.wi.gov/files/PDF/pubs/wa/WA1585.pdf