Sowing in the open
ContentThe success of sowing outdoors depends greatly on preparing the seedbed; the tilth needs to be matched to the type of seed, soil texture and the expected weather conditions. The area to be prepared should be free draining. It is thoroughly dug or ploughed depending on the scale of operation. Weeds are buried and organic matter is incorporated in the process. Ideally this is done in the autumn especially if it is a heavy soil; the raw soil is then exposed to the action of frost and rain. In the spring the mellow, weathered, soil is knocked down with rake or harrow to form the right tilth that provides water and oxygen for seed germination; broad beans can be sown into a very rough seedbed very early in the spring whereas smaller seed sown into warmer conditions should go into a much finer tilth. Weeds need to be dealt with by creating a false or stale seedbed, hoeing or using weedkillers. Nutrients, especially phosphate fertilizer, are worked in and the ground levelled to receive the seed. Seed are usually sown in rows (drills) or broadcast, depending on the circumstances. Some seeds will more appropriately be station sown. On a larger scale, seeds are drilled with appropriate equipment. Seeds should be at the right depth, covered to their own diameter and sown when ground temperatures are suitable for the plants concerned. The sowing rate will depend on the species and the likely losses, which can be estimated from the field conditions, the germination percentage and the viability of the seed There are advantages to providing protection for the developing plants in the form of windbreaks or floating mulches. Where residual herbicides are not used there needs to be ongoing control of emerging weeds while they are in competition with the seedlings and young plants. If the seedbed was well watered then there should, normally, be no further need to irrigate; indeed there are advantages in not doing this in terms of water conservation, to encourage deeper rooting and prevent capping of the soil. |