SOWING AND GROWING VEGETABLES
This section explains the general principles ofindoors. There are basic elements of sowing seed and cultivating the plants which are common to all types. To ensure the success of a particular crop, however, it is important to follow the details given in later sections for each individual vegetable as the details of cultivation at each stage vary from plant to plant.
Choice of seeds
The size of seed for the range of vegetables varies considerably; some are tiny and difficult to sow evenly, others quite large and easy to handle. If you buy an ordinary packet of seed, the quantity of seeds in the pack varies correspondingly, but for any type of plant, this is the most economical way of buying seed. You can alternatively use pelleted seeds; each seed is enclosed in an outer casing which disintegrates once it is sown into the damp. These are larger and more uniform in size, so it is possible to space them quite carefully and avoid wastage in thinning out the growing . However, because of their size there are fewer to a pack. They are more costly than ordinary seeds, so it is a matter of deciding whether you would rather have the convenience or the greater economy, depending on the size of crop you intend to raise and the number of seeds you may be able to use during one season.
To store seeds between sowings, leave the remainder in the packet and put this into an airtight screw-top jar, to prevent the seeds from being affected by moisture in the atmosphere. Store the jar in a cool place. Pelleted seeds keep for up to two years, but it is unwise to keep ordinary seeds for too long, as a relatively high percentage will not germinate successfully after a period of time. With the longer growing season for indoor vegetable gardening and the practice of succession sowing of small quantities, it should not be necessary to keep seed from one year to the next.
The growing medium
For container gardening the growing medium needs to be free-draining but moisture-retentive, with a firm but open texture that allows the plants’ roots to spread and find anchorage. If you have access to a supply of garden soil, this can be used as the basis of your own soil mixtures. Sieve it carefully to remove large clumps of earth and stones, and make sure it is free of weed roots and. You can obtain commercially-produced bags of sedge peat, silver sand and humus, and also odour-free manure. These can be mixed into the soil in varying quantities to improve the texture and nutrient content.
It is simpler for the inexperienced gardener to buy large bags of good-quality potting mixture. There are several proprietary brands to choose from, and a reputable manufacturer will have ensured that the mixtures have balanced nutrient content and are free of soil-borne diseases and weed spores. Soil-based mixtures are also described as loam-hased, loam being a type of good soil. The alternative is peat-based mixtures, also called soilless mixtures; these are generally more fibrous in texture and dry out more quickly than the soil-based types. Additional material such as sand and humus can be added to these commercially produced growing mediums to improve the drainage and moisture-retention as necessary.
You will find proprietary mixtures intended only for sowing and germinating seed. There are not formulated to supply the needs of a developing plant, so seedlings are then potted up into a slightly coarser and more nutritious growing medium, possibly through two or three grades until the plant is fully established. There is no advantage to using a sowing mixture for germinating vegetable seed and it is more efficient to select a good all-purpose growing medium at the start, which you can use for both sowing and potting on.
After harvesting your produce, the spent soil can be reused as the basis of a new soil mixture for new plantings. Turn out the pottings into a large plastic bag, remove any roots remaining in the soil and blend in some peat, humus and manure to improve the texture and replace lost nutrients.