Every fall I warn about cutting alfalfa during its winterizing period. Since you may have quite a bit of growth available now, let’s discuss how you can do it most safely.
During early fall, alfalfa plants detect that the amount of sunlight each day is getting less. This tells them that winter is coming so they change their growth process to winterize.
If you cut your alfalfa during this winterizing period, the plant begins to regrow. This reduces its ability to winterize as fully as it would if it hadn’t been cut.
But we all know from experience that alfalfa cut in late September or early October often survives just fine, although spring growth may be a little slower. Is there any way you can increase the chance of your alfalfa surviving and growing well next spring?
First and foremost, make sure your alfalfa gets a chance to grow well for a long time in late summer to build its root nutrient reserves. Allow at least six weeks between your previous cutting and the cut that occurs during winterization. This is especially critical if the field was cut five or more times this year.
Second, thoughtfully select fields to be cut during winterization. Avoid old, thinning fields unless you plan to rotate that field to a different crop next year. Young, healthy alfalfa fields containing varieties with good winter survival ratings are most likely to perform well even after cutting during winterization.
Lastly, consider waiting to cut until mid-October, after winterization is over or plants are nearly dormant. The stress of regrowth following this extra late cutting usually is very small.
Valuable alfalfa often is available to cut this time of year. Careful harvest will help assure it also is there again next year.