How to Grow Herbs Indoors: A Complete Guide to Basil, Mint, Rosemary and More

Supermarket herb packets are convenient, but they come with real limitations. Herbs begin losing their volatile aromatic oils the moment they are cut, which is why shop-bought basil often tastes flat compared with a leaf picked seconds before eating. When you grow herbs at home, you harvest exactly what you need, exactly when you need it — a handful of chives for scrambled eggs, a few thyme sprigs for a roasting tray, a full bouquet of coriander for a Thai curry.

The difference in flavour is measurable. The essential oils that give herbs their aroma — linalool in basil, thymol in thyme, menthol in mint — are most concentrated in freshly picked leaves that have had time to develop on the plant. Home-grown herbs, harvested just before use, can have two to three times the aromatic intensity of pre-packaged equivalents.

Beyond flavour, growing your own herbs changes your relationship with cooking. When you have a pot of tarragon on the windowsill, you start reaching for it. You experiment. You add it to a cream sauce on a Tuesday night not because a recipe demanded it but because it is there. That instinctive, ingredient-led cooking is the hallmark of confident home cooks everywhere.

You do not need much space to grow a meaningful herb collection. A windowsill 60 cm wide can comfortably hold four to six medium pots. The single most important factor is light: most culinary herbs are Mediterranean in origin and want at least six hours of direct sunlight per day. A south-facing window in the northern hemisphere is ideal; east- or west-facing will work for less demanding herbs like mint, parsley and chives.

If your home is short on natural light, a small LED grow light positioned 15–30 cm above the pots for 14–16 hours per day will compensate fully. Modern full-spectrum LED panels use very little electricity and are widely available.

For containers, terracotta pots are traditionally favoured because they are porous and help prevent waterlogging, but any pot with drainage holes will work. Avoid pots without drainage — stagnant water at the root zone is the primary cause of herb death indoors. A 10–15 cm diameter pot suits individual herbs; a 20–25 cm pot can hold a mixed planting of compatible companions.

Soil matters enormously. Standard multi-purpose compost retains too much moisture for Mediterranean herbs. Use a free-draining mix: two-thirds multi-purpose compost to one-third perlite or horticultural grit. For moisture-loving herbs like mint, basil and coriander, plain multi-purpose compost is fine.

Not all herbs are equally forgiving indoors. These are the most reliable starting points:

**Basil (Ocimum basilicum)** — 'Genovese' is the classic large-leaved Italian variety, ideal for pesto and caprese. 'Sweet Thai' offers a spicy anise note perfect for Asian cooking. Basil is warmth-loving and will collapse below 10°C, so keep it away from cold draughts.

**Mint (Mentha spp.)** — Spearmint ('Mentha spicata') and peppermint ('Mentha x piperita') are the most useful culinary mints. Grow mint alone — it spreads aggressively and will crowd out neighbouring plants. Moroccan mint makes exceptional tea.

**Rosemary (Salvia rosmarinus, formerly Rosmarinus officinalis)** — 'Arp' and 'Tuscan Blue' are compact, upright varieties well-suited to containers. Rosemary is drought-tolerant and resents overwatering more than almost any other herb.

**Thyme (Thymus vulgaris)** — Common thyme and lemon thyme ('Thymus x citriodorus') both thrive in pots with very free-draining soil. Lemon thyme is particularly versatile in fish and chicken dishes.

**Chives (Allium schoenoprasum)** — Extraordinarily easy, tolerant of lower light levels, and useful in everything from omelettes to potato salads. Garlic chives ('Allium tuberosum') offer a mild garlic flavour.

**Parsley (Petroselinum crispum)** — Flat-leaf (Italian) parsley has superior flavour to the curly variety. It is a biennial, so expect one strong season of growth.

**From seed:** Fill a small pot or seed tray with moist seed compost. Scatter seeds thinly across the surface — most herb seeds are tiny, so thin sowing prevents overcrowding. Cover with a fine layer of vermiculite (2–3 mm) and place in a warm spot (18–22°C). Basil germinates in 5–7 days; parsley can take 2–3 weeks. Once seedlings show their first true leaves (the second pair after the initial seed leaves), thin to the strongest plant or prick out into individual 7 cm pots.

**From cuttings:** Rosemary, mint, thyme and sage propagate very easily from stem cuttings. Take a 10 cm cutting just below a leaf node, remove the lower leaves to leave a bare 5 cm stem, and push into moist cutting compost or even a glass of water. Roots appear in 2–4 weeks for mint; 4–6 weeks for woody herbs like rosemary.

**From supermarket pots:** Many people start with potted herbs from the supermarket — these are cheap but heavily overcrowded with dozens of seedlings crammed into a single pot. Split them into 3–4 smaller clumps immediately and repot each into its own 10 cm pot. Cut back by a third to reduce stress. Most will recover within two weeks and then grow vigorously.

**Watering** is the skill most beginners take longest to master. The rule for Mediterranean herbs (rosemary, thyme, sage, oregano) is to water thoroughly, then let the top 2–3 cm of soil dry out completely before watering again. For moisture-loving herbs (basil, coriander, mint, parsley), keep the soil consistently moist but never waterlogged. Always check the soil with your finger rather than watering on a schedule.

**Feeding** is only necessary once herbs are established and growing actively. Use a balanced liquid fertiliser (such as a tomato feed diluted to half strength) every two weeks from spring through summer. Avoid overfeeding — excess nitrogen produces lush growth but dilutes the concentration of aromatic oils, which actually reduces flavour intensity.

**Pruning** is crucial and counterintuitive for beginners: the more you harvest, the bushier and more productive the plant becomes. For basil, pinch out the central growing tip as soon as the plant reaches 15 cm tall to encourage branching. Remove flower buds the moment they appear — once basil flowers, it puts energy into seed production rather than leaf growth, and the leaves turn bitter. For woody herbs like rosemary and thyme, a light trim after harvesting keeps the plant compact and prevents it becoming leggy.

Herbs are best harvested in the morning after any surface moisture has dried, when aromatic oil content is highest. For soft herbs (basil, mint, parsley, chives), simply snip stems just above a leaf pair or node. Never remove more than one-third of the plant at a single harvest — leaving two-thirds allows rapid regrowth.

For woody herbs (rosemary, thyme, sage), use sharp scissors or pruning snips to cut back to just above a healthy leaf or bud. Avoid cutting into bare, woody stem that has no leaves — woody stems rarely re-sprout.

Fresh herbs keep best at room temperature in a glass of water, like cut flowers, covered loosely with a plastic bag. Basil is particularly sensitive to cold and should never be refrigerated — it turns black within hours at temperatures below 10°C. Parsley, coriander and mint can be refrigerated in water for up to a week.

For longer storage, chives, parsley and coriander freeze well: wash, dry, chop finely, pack into ice cube trays with a little water or olive oil, and freeze. Rosemary, thyme and sage are better dried: tie stems into small bundles and hang upside down in a warm, well-ventilated room for 1–2 weeks, then strip the leaves and store in airtight jars.

Fresh basil is most famously used in pesto (blended with pine nuts, Parmesan, garlic and olive oil) and caprese salad, but it shines equally in Thai green curry, Vietnamese pho, and torn over pizza straight from the oven. Basil oil — warm olive oil gently infused with fresh basil and strained — keeps for two weeks in the fridge and transforms simple pasta dishes.

Fresh mint is essential in tabbouleh, raita, mojitos and Middle Eastern lamb dishes. Mint sauce for roast lamb takes about five minutes to make: finely chop mint leaves, dissolve a teaspoon of sugar in two tablespoons of boiling water, add three tablespoons of white wine vinegar and mix — infinitely better than jarred.

Rosemary-infused olive oil is one of the most useful preserves you can make: bruise a few sprigs, add to a small saucepan of good olive oil, warm very gently for 20 minutes (do not boil), strain and bottle. Use for roasting potatoes, drizzling over bread or marinating chicken.

Thyme pairs beautifully with mushrooms, lemon and white wine in pasta sauces, and is indispensable in a classic bouquet garni alongside bay and parsley stalks. Chives, snipped over crème fraîche-dressed jacket potatoes or folded into scrambled eggs, are among the simplest pleasures home growing offers.