Crimson clover is usually sown between August 15 and October 1, the general rule being to plant about 60 days before the first killing frost is expected. South of Virginia crimson clover can be seeded as late as November 1, although if planted late more seed should be used and a light dressing of nitrate of soda applied, in order to stimulate the young plants. Seeding earlier than August 1 is seldom advisable unless the crop is sown with some other crop the shade of which will hold it back.
The exact date of planting depends almost entirely upon the moisture content of the soil. The principal condition to avoid is planting when the soil contains just enough moisture to germinate the seeds, but not enough to keep the plants growing. Usually it is better to plant when the soil is quite dry than when it is slightly moist, for in dry soil the seeds, if properly buried, lie without germinating and are ready to grow vigorously at the first rainfall. The most favorable time for seeding is just before or just after a good rain, when the soil is moist enough to form a ball in the hand.
RATE OF SEEDING.
The ordinary rate of seeding crimson clover is 15 pounds per acre, although the rate varies according to conditions. From 12 to 15 pounds per acre are usually sufficient when growing the crop for seed or when the soil is unusually rich. On poor soil, dry soil, or on soil which has not previously produced crimson clover 18 to 22 pounds of seed give better assurance of a stand. Heavy seeding is also desirable when planting late in the season or when a heavy crop is wanted for green manure early in the spring.
Theoretically, 2 pounds of seed per acre would provide six plants for every square foot, which is a satisfactory stand. Under ordinary circumstances, however, it is necessary to allow for some of the seed being too deep, or too shallow, or failing to germinate, and for a certain percentage of winterkilling. It is also well to have a fairly thick stand of the young plants, so that the ground may be well covered during the early fall and thus prevent soil washing and the growth of winter weeds.
METHODS OF SEEDING.
The most common method of seeding crimson clover in intertilled crops is to scatter the seed broadcast with a rotary seeder or by hand. ([Fig. 6.]) In order to place the seed on a fresh, moist seed bed it is commonly broadcasted immediately behind the cultivator at the last cultivation and is covered 'at once by a second cultivator. In tall corn the seed may be sown from horseback, the ears of the horse being covered with small bags to prevent the entrance of the flying seed. Slightly more seed is required when seeding in tall corn, as some seed catches in the corn plants. When seeding in cotton care must be taken to avoid injury to the opening bolls, which are easily knocked off or torn. This is best done by seeding by hand, covering the seed with a piece of brush dragged down the rows.
In low-growing truck crops and on fallow ground crimson clover can be seeded with a wheelbarrow seeder. This implement distributes the seed more evenly than can be done by hand or with the rotary seeder, especially when planting a mixture of crops. The wheelbarrow seeder being somewhat awkward to handle is better adapted to smooth, level fields than to hillsides.