The 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.