Growing Herbs on a Kitchen Windowsill

Why the Kitchen Windowsill Is the Best Spot in the House

Most herbs we grow on a windowsill come from the Mediterranean or from mild, sheltered places, and a bright kitchen suits them surprisingly well. The glass gives you light, the room gives you warmth, and the kettle gives you an excuse to check on things twice a day. A south- or west-facing sill is ideal, offering six or more hours of daylight through spring and summer. East-facing sills work well too, particularly for parsley and chives, which are happy with gentler morning sun.

There are two things to watch. First, the temperature swing: a sill behind glass can become an oven on a sunny July afternoon and a chilly spot on a frosty January night. Second, dry air from radiators. Both are manageable, and we will come to them. The great advantage of the kitchen sill is simply that you see the plants every day, so small problems get caught while they are still small.

Which Herbs Earn Their Place

• Basil is the classic windowsill herb. It wants warmth, plenty of light and steady moisture. It sulks below about 10°C, so keep it away from cold draughts and single-glazed panes in winter.
• Parsley is tougher and far more forgiving of a slightly shaded sill. Flat-leaved types have the best flavour, but curled parsley looks cheerful and crops for longer.
• Chives are the most reliable of the three, happy to be cut repeatedly and quite content with a little less sun. The purple flowers are edible and lovely scattered over salads.
• Also worth a pot: mint (keep it in its own container, as it spreads), thyme, oregano and coriander. Coriander runs to seed quickly in heat, so sow it little and often.

You can raise herbs from seed, buy young plants, or rescue a supermarket pot. Those dense supermarket basil clumps are really dozens of seedlings crammed together — split them into three or four pots and each will grow into a proper plant rather than collapsing within a fortnight.

Compost and Containers: Drainage Comes First

Herbs detest soggy roots, and the single most common cause of a sad windowsill herb is compost that stays wet. Use a free-draining mix: a good peat-free multipurpose compost with a handful of horticultural grit or perlite stirred through works well. For thyme, oregano and rosemary you can go half and half.

Every pot needs drainage holes, and a layer of broken crocks or gravel in the base helps water move away from the roots. Terracotta looks handsome and dries out faster; plastic holds moisture longer and is lighter on a sill. Either is fine — just adjust your watering to suit. Aim for pots around 15cm across for a single herb, larger for parsley, which develops a long taproot.

If you can, raise pots slightly on pebbles or small feet so they are not sitting in a puddle. That one detail prevents more grief than almost anything else.

Watering from the Base, Not the Top

Watering from below encourages roots to grow down and keeps foliage dry, which reduces mould and fungal problems. Stand the pot in a tray or saucer of water for fifteen to twenty minutes, then tip away whatever has not been taken up. Never leave a pot standing in water for hours.

Check the compost before watering by pushing a finger in to the first knuckle. Water when it feels dry at that depth. In summer that may be every day or two; in winter, once a week may be plenty. Basil and parsley prefer to be kept evenly moist rather than alternating bone dry and soaked. Chives are more tolerant of occasional drying out.

If your tap water is heavily chlorinated, fill a jug and let it stand overnight before using it. It is not essential, but basil and parsley seem to appreciate it.

Pinching, Cutting and Feeding for a Long Harvest

Regular picking is what keeps these plants productive. Left alone, basil will simply grow upwards, flower and give up.

• Basil: pinch out the growing tip just above a pair of leaves. Two new shoots will break from that point, and the plant becomes bushy rather than leggy. Do this every couple of weeks and remove flower buds as soon as you see them.
• Parsley: harvest the outer stems at the base, leaving the inner crown to keep producing. Never strip a plant bare in one go.
• Chives: snip leaves with scissors about 2–3cm above the compost. Cutting into the white base will set the plant back badly.

Feed with a weak liquid fertiliser every fortnight from spring to late summer — roughly half the strength recommended on the bottle. Overfeeding makes soft, floppy growth with less flavour, so err on the mean side. In winter, stop feeding altogether and let the plants rest.

Keeping Plants Healthy Through the Year

Aphids and whitefly are the usual invaders. A firm squirt of water from a spray bottle dislodges them, and checking the undersides of leaves weekly catches an infestation early. Small black flies hovering around the compost are sciarid flies, almost always a sign of overwatering — let the surface dry out and they will fade away.

Mould on leaves points to poor airflow and wet foliage. Space pots out, avoid misting, and open a window when the weather allows. In winter, move pots back from the glass on frosty nights and reduce watering sharply. Basil often declines in low light; rather than fighting it, take cuttings in late summer or sow fresh in spring. Parsley and chives will usually sit quietly through the winter and reward you with fresh growth as the days lengthen.

Rotate your pots a quarter turn every few days so plants grow straight rather than leaning towards the glass. It takes seconds and makes a noticeable difference to how your little kitchen garden looks and crops.