Forages planted as early as possible in September survive winter better and produce higher yields than those planted later, according to Marvin Hall, Penn State University Extension forage specialist.
Seeding them at the right depth and with good soil contact are important, too, he says.
The two graphs below show what a grower can expect as planting dates move later and later toward fall. “Planting alfalfa between Sept. 1 and Sept. 15 in central Pennsylvania and after Sept 15 in southeastern Pennsylvania resulted in poor winter survival and low yields the year after planting,” Hall says.
“Orchardgrass did a little better when planted in late September but still didn’t have much vigor or yield the following year.”
Whether forages are planted no-till, with conventional tillage or broadcast, make seeding depth and seed-to-soil contact top priorities, he adds.
“Planting forage seeds too deep can exhaust the energy reserves in the seed before the new seedling has emerged.” That causes poor seedling establishment, which can increase weed competition, lower forage yields, and ultimately shorten stand life. He recommends planting forages about ¼” deep. Planting more than ½” deep will lower seedling emergence by as much as 50%.
Good seed-to-soil contact ensures that the seeds can absorb adequate water from the soil to germinate. Poor contact slows water absorption and allows water to evaporate out of the seed, Hall says.