Container Vegetable Gardening: Transplanting and Potting On
As thedevelop and the growth begins to spread, they should be moved on to larger containers. One plant per pot is the ideal, but if you are short of space, three or four seedlings can be transplanted into a larger pot and may be potted on again at a later stage if the container is not large enough to support them all. Remember that the point of using larger containers is not only to provide room for the top growth, but also for the roots which are establishing within the . It is often more important that the plants are given greater soil depth as they grow, rather than space to spread laterally.
The first pair of leaves which appear after germination are the cotyledons, or seed leaves, which contain the young plant’s food supply. The first transplanting should be made when the seedlings have developed at least two or more true leaves after the appearance of the cotyledons. Prepare the new container before you lift the seedlings, firming in the potting mixture and making a hole in the soil to receive the tiny plant. It can be difficult to grip the fine stem of a seedling without causing damage. A kitchen fork is a useful implement for transplanting: slip two tines of the fork around the main stem of the plant just below the cotyledons, and use the fork to lift the seedling gently. You may need to loosen the soil carefully to work the seedling free; a plant label is useful for this task, but be careful not to cut through delicate roots when you disturb the potting mixture.
Lower the seedling into the new container and lightly press the soil around the roots and plant base to anchor it well in position. Water the soil very moderately with tepid water, carefully applied to avoid wetting the plant. Place the containers in a light position, but do not put seedlings in full sun where they will be scorched. If the plants are on a brightly lit windowsill, put newspaper between the container and window pane to shade the seedlings during times of day when the sun is strongest.
Unless you have been able to move the seedlings directly into their final containers, they should be potted on again when four or more leaves have developed around the central growing point. Continual repotting is not encouraging to the plants’ growth, and root disturbance is usually resented at any stage. If the plants seem a little sluggish after transfer to a new container, leave them time to re-establish and resume growth. Do not supply extra water or fertilizer in the hope of reviving them; this runs the risk of doing more damage through over-watering and scorching of the roots.
Low-or those which do not produce branching growth present no problems in container growing. The larger varieties can become quite heavy, the more so as the fruits set and develop towards harvest. Tomatoes, , beans and are among the plants which require some form of support from quite an early stage. Cucumbers are also among those plants which actually produce a better crop if well-supported.
A tomato plant is adequately supported when tied in to a single sturdy cane. Melons require a construction of canes and wire which trains the lateral shoots horizontally, and the heavy fruits need the support of nets. The method of support for each vegetable is explained under the relevant heading.
Sex is essential even in the vegetable garden. If the seeds are not pollinated – fertilized by the pollen of the male flowers – then there will be no development of fruits, and a number of the vegetables which you may wish to grow are technically the fruits of the plant. There is a general exception to this rule in the case of all-female hybrid plants, which do not require pollination. Several of the recommended cultivars are of this type and you should keep a note when you are ordering seeds as to the category of the plant for reference when the time comes for pollination.
If your plants are growing outside on a patio, rooftop or balcony when they come into flower, all well and good: the bees will find them and they will be pollinated naturally. But in the indoor kitchen garden, you will have to do the bees’ job for them, fertilizing the plants by hand-pollination.
Pollination is essential to the productivity of melons, aubergines,and other delicacies. You will need to study the flowers to identify the male and female parts. In the large flowers of the , for example, these are easy to see. The male flower is dissected down the middle; the anthers are the male sexual parts which contain the pollen grains. In the female, there is a swelling at the base of the flower (the future courgette) containing the ovules, or unripe seeds.
On pollination, during which the fine, dust-like pollen is deposited on the stigma (the sticky top of the style in the female flower) each pollen grain sends a microscopic tube down into the ovary, travelling down inside the style until it reaches one of the ovules. The tube penetrates the ovule and fertilizes it; this, when it ripens, becomes the seed. This is sexual reproduction, as distinct from propagation of plants, and this brief biology lesson helps to explain what it is you are doing when you hand-pollinate a plant.
The method illustrated here is a general guide which should ensure good results. In a few cases I recommend a different pollination method — for tomato plants, for example – when the flowers are small and difficult to handle. The alternative process is simply to spray the plants well on several successive days once the flowers have begun to open. This serves to disperse the pollen and the repeated sprayings take account of the fact that the flower buds on a single plant will be opening over a period rather than all at once.
There are a few cases in which male flowers on the same plant as the female should not be allowed to pollinate it; in this case, you just remove the male flowers to make sure that the pollen which reaches the stigma has come from a male flower of another plant, or hand-pollinate from plant to plant.
Pests and diseases affecting vegetable gardening
The relative lack of trouble fromand pests is another advantage of indoor growing but cannot be discounted altogether, especially during fine weather when you may wish to keep windows and doors open or stand the containers outdoors. Slugs and snails enjoy leafy-growth of all kinds and may be found under the rim or on the soil of containers placed outside; they also from time to time come indoors through an open window. These are easily seen, however, and removed. If you bring containers back inside from an outdoor position, check that you have no unwelcome visitors.
Bean crops are susceptible to blackfly, though I have never found this a problem with indoor gardening. Should you discover these tiny black aphids infesting your plants, you can remove them effectively without resort to chemical pesticides. Use ordinary soap and water to create a good lather and spray the foam forcefully on to the affected stems and on leaves. The blackfly will not survive this treatment, but it will do no damage to the plants.
Aubergines are commonly troubled by red spider mite. Fortunately, these too are less likely to attack container-grown plants, but if they do, they can be defeated by nothing more lethal than tepid water. Spray generously until the pests disappear; this treatment is also good for the plant, which needs a warm, moist atmosphere.