Starting a Small Herb Garden on a Kitchen Windowsill

Why a kitchen windowsill earns its keep

A windowsill is the smallest growing space there is, and it gives back far more than you would expect. A few pots of basil, parsley and chives will keep you in fresh snippings from spring to autumn and save you buying those sad bags of cut herbs that turn to slime in the fridge. Treat it as a proper growing space rather than somewhere to park a supermarket pot and hope for the best.

Light decides everything. A south-facing sill suits basil and coriander best. East and west-facing windows are kinder, giving softer light without scorching tender leaves on a hot afternoon. If all you have is a north-facing sill, choose parsley, chives and mint, which cope with lower light, and expect slower growth.

Choosing herbs that suit a pot

Not every herb belongs on a sill. Rosemary, bay and sage want more root room and more light than most kitchens offer, and they go woody and sulky. Stick to compact, leafy herbs you can cut often.

• Basil — pick a compact bush or Greek basil; the big-leaved types grow tall and flop.
• Parsley — flat or curled, both fine. Slow to germinate, then crops for months.
• Chives — the most reliable of all; snip and they regrow. A garden clump potted up in autumn works well.
• Mint — always in its own pot, or it swamps everything. Spearmint is best for cooking.
• Coriander — quick and rewarding, but it bolts in heat, so sow little and often.
• Thyme — slower, but perfectly happy in a small pot on a sunny sill.

Pots, compost and sowing

Use pots at least 9cm across with proper drainage holes, stood on a saucer to protect the sill, and fill them with peat-free multi-purpose compost mixed with a handful of grit or perlite. Herbs hate sitting in soggy, airless compost.

Sow thinly. Basil needs light to germinate, so press the seed into the surface and barely cover it; at 20–22°C it is up within a week. Parsley is the opposite — slow, sometimes three or four weeks, so keep the compost just moist rather than wet. Chives take about a fortnight. Once seedlings have their first true leaves, thin them to the strongest few, pinching out the rest rather than pulling, which disturbs the roots you are keeping. Label everything with the date; you will forget.

Light, water and feeding on a windowsill

Most windowsill herbs fail for one of two reasons: too little light, or too much water. Turn pots a quarter-turn every few days so they grow straight rather than leaning at the glass. Pale, spindly, stretched seedlings need more light, not more feed.

Water from below where you can — stand the pot in a few centimetres of water for ten minutes, then tip the rest away. Little and often beats a weekly flood, and pots should never sit permanently in a full saucer. Feed lightly with diluted liquid seaweed or tomato feed once a fortnight in summer, and not at all in winter, when growth slows.

Harvesting so they keep producing

Regular cutting keeps herbs bushy. Pinch basil just above a pair of leaves, and never strip more than a third of a plant at once. Take parsley from the outside of the clump so the centre keeps growing. Snip chives about 2cm above the compost and they shoot again within a fortnight.

For a steady supply, sow a small pot of basil or coriander every three to four weeks from March to August, rather than one big pot that gives you a glut and then nothing. In summer, herbs often do better spending a fortnight outside on a sheltered step; the extra light and air toughens them up before you bring them back in.

Common snags and how to head them off

• Leggy, pale seedlings — too little light. Move them to a brighter sill and start again in spring rather than midwinter.
• Mould on the compost surface — too wet and too airless. Scrape it off, water less, and stop covering the pot.
• Fungus gnats — the little black flies that hover over pots. They breed in permanently wet compost, so let the top centimetre dry out between waterings.
• Greenfly and whitefly — wipe them off with a damp cloth, and check any new plant before bringing it indoors.
• Wilting despite wet compost — usually drowned roots. Repot into fresh, freer-draining compost and ease off the watering can.

Come autumn, chives and parsley usually keep going on a cool, bright sill, giving you a few leaves through winter. Basil will not — treat it as a seasonal crop, sow again in February, and enjoy what a windowsill does for a bowl of pasta or a plate of scrambled eggs.