September 11, 2009

During early fall alfalfa plants detect the decreasing sunlight and adjust their growth process to winterize themselves.

If you cut alfalfa during this winterizing period, the plant begins to regrow. This reduces its ability to become as fully winterized as it would be without a cutting.

We all know from experience that alfalfa cut in late September or early October often survives just fine, although spring growth might be a little slower. To increase the chance of your
alfalfa surviving and growing well next spring, take these steps:

• First and foremost is to 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 even more critical if the field gets 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.
• Third, consider waiting to cut until mid-October, after winterization is over or plants are nearly dormant. The stress of regrowth following thisextra late cutting usually is small.

When you cut your alfalfa this fall, taking a few careful steps can help ensure you’ll also have a good harvest next year.
Bruce Anderson
Extension Forage Specialist