THE INDOOR HERB GARDEN
Herbs are among the most rewarding of food crops for indoor growing. They produce results quickly and besides adding their aromatic and distinctive flavour to hot and cold dishes of all kinds, they make an attractive display growing in pots on a sunny windowsill. There are some herbs, both popular and unusual varieties, which are not suited to container growing indoors, because they need a steady high temperature or plenty of root space to develop useful growth; but there is an excellent range of widely enjoyed herbs which can be readily propagated and grown under indoor conditions.
The indoor growing conditions for herbs are much the same as those generally required for most houseplants; a reasonably even temperature in a well-lit, fairly humid location, with protection from extremes such as fierce direct sun or low night-time temperatures. The right environment is easy to attain during summer months, but some herbs can be grown through the winter to provide fresh, leafy growth, and will need a little more care when indoor and outdoor temperatures are highly-contrasted – they should be grown at or very close to a window to take advantage of all available light, but should not be exposed to cold currents of air or allowed to stand with their leaves pressed against frosted window panes.
Cultivation of herbs
Most of the herbs recommended here can grow well in small to medium-sized pots so need not take up much space; alternatively you can plant them together in a trough or box. They look pretty in earthenware containers, includingand strawberry pots which have holes in the pot sides through which the plants can grow as well as the wider opening at the neck of the pot. A few need a good depth of for adequate root development, while others thrive in confinement; the best conditions are described for each individual herb. Container growing tends to restrict plant growth, so the herb plants do not attain the height and spread that they would achieve in the open garden. But this can be a positive advantage, as in the case of mint, which in the open garden rapidly spreads across all the available space, and with the bushy or shrubby types, such as thyme, rosemary and bay, which can be clipped and controlled to encourage a compact shape and fresh new growth.
Good drainage is essential, as too much moisture at the roots is inevitably damaging. Make sure that the potting medium is free-draining; you can stand the containers on a tray of pebbles so that the moisture escaping from the bottom of the pots contributes to a moist atmosphere around the growing plants. Provide a good-quality soil-based growing medium: container-grown herbs rapidly extract the nutrients from the soil and may benefit from occasional feeding during the period of full growth.
Using herbs in the kitchen
The main purpose and advantage of growing herbs indoors is of course to have fresh leaves immediately to hand for flavouring cooked dishes and salads. (If you keep the herb pots in the kitchen, make sure they are out or range of gas fumes, concentrations of steam and the radical changes of temperature caused by cooking appliances.) Salads, sandwiches, snack foods, roast meats, casseroles and stews, and vegetarian dishes all benefit from the true taste of fresh herbs. But if your crops do well, you may also wish to store some of the produce, and the leaves can alternatively be dried or stored in the freezer.
Leaves for drying should be spread on an absorbent surface, not on wire racks; a piece of muslin stretched over a wooden frame makes an ideal drying rack for herbs. Allow them to dry in warm, airy conditions, but not in direct sun, to maintain colour and flavour. Dry whole sprigs of the herbs and strip leaves from stems after they are dry. Store the leaves in airtight containers, to prevent re-absorption of moisture, where they will keep for six to eight months.