Sowing your seeds directly into the ground is the easiest way to do it, provided the temperature, dampness and condition of the soil are suitable for the variety of seeds to be sown.
Do not get caught out in late March when a well known cold spell frequently occurs with sleet, snow and cold winds. There are many ancient folklore tales about the likelihood of extreme cold at the end of March. There is the rhyme :- March borrowed from April, Three days and they were ill, The first was Snow and sleet, The next was cold and wet, The third was such a freeze, The birds’ nests were stuck to trees.
There is also meteorological evidence for this pattern.
Condition of the soil. The soil should have been dug, weeded, fertilized several weeks before and allowed to settle. For early sowings, it is best if the soil has been warmed up for several weeks, by covering the ground with black polythene or a tarpaulin. From your schooldays in the science lab, you may remember that black objects best absorb the heat of the sun. The polythene also will stop any late, night frosts penetrating the ground. Alternatively, you could cover the seed bed with cloches for 2 weeks before sowing seed.
Just prior to sowing the seed, make sure that the top 3 cm of soil has been raked to a fine tilth.
Temperature of the soil. Different varieties of seeds each have an optimum minimum temperature for easy and quick germination of the seed. If the soil is too cold, the seed will not germinate and will probably rot. If you are sowing in April and May, covering the seed bed with cloches will keep the temperature higher and help germination.
Aim for a minimum soil temperature of 8-10 C to germinate the hardiest seedlings such as alliums, brassicas, peas and beans, although the germination will be slow. The higher the temperature, the quicker the germination of the seeds will be. This soil temperature should also be suitable to start planting early potatoes.
To check the temperature, use a soil thermometer. If not available, try this method. From weather reports for your area, take an average of the maximum daytime temperature for a week.
Similarly, take an average of the minimum nighttime temperature for a week. An average of the daytime and the nighttime temperature will give a rough guesstimate of the likely temperature of the soil at up to 5 cm depth.
Dampness of the soil. Seeds need a continuous supply of moisture to germinate and continue to grow. Therefore make sure that the soil is damp before you sow the seeds, and inspect regularly afterwards and water as necessary.
For most types of small seeds, such as lettuces, you should form a narrow furrow with a rake or trowel, some 1 cm deep, and sow your seeds at the suggested spacing on the seed packet. Now fill in the furrow with fine soil, using the rake or trowel, lightly tamping the soil down with the back of the rake. Water the soil with a watering can fitted with a fine rose, and label the row, as you are sure to forget the name of the variety.
For large seeds, such as peas and beans, gently dig out a shallow drill, some 5 cm deep and the width of the spade. Sow a double row of seeds at the spacing recommended on the packet, and refill the drill with fine soil before tamping it firm. Now water the soil with a watering can, fitted with a fine rose, and label the row.
For continuity of cropping, try sowing one half of the row of a vegetable in April and another half row in July. This is particularly useful for salad crops, peas and beans. Also try sowing a few seeds of several varieties that have different cropping times to spread the period of cropping. There is nothing worse for the amateur vegetable grower, than to have a dozen of the same vegetable all to be ready for picking at the same time. The open pollinated (non F1) seed varieties, tend to have more variation in their picking times, while F1 varieties tend to crop all together at the same time.