Growing Herbs Indoors: How to Keep a Windowsill Herb Garden Actually Alive
An indoor herb garden is one of the most satisfying small growing projects there is — fresh basil or coriander within arm's reach of the chopping board never gets old. It's also one of the easiest things to accidentally kill, usually through a combination of too little light and inconsistent watering.
Light Is the Biggest Factor
Most culinary herbs, particularly Mediterranean varieties like basil, rosemary, and thyme, want as much direct light as an indoor spot can offer, ideally a south-facing windowsill that gets several hours of direct sun. A north-facing windowsill, however pretty it looks, usually isn't bright enough to keep most herbs happy long-term, and plants grown there tend to become leggy and pale as they stretch towards whatever light they can find.
If natural light is genuinely limited, a simple grow light positioned above the herbs for ten to twelve hours a day can make the difference between a thriving herb garden and a slowly fading one, especially through autumn and winter when daylight hours drop.
Choosing the Right Herbs to Start With
Some herbs are simply better suited to indoor life than others. Basil, mint, chives, and parsley are relatively forgiving and grow well in pots on a bright windowsill. Rosemary and thyme prefer it on the drier side and can struggle indoors if overwatered, but do well once you understand their preference for letting the compost dry out between waterings. Coriander is trickier indoors and tends to bolt (flower and go to seed) quickly if it gets too warm or doesn't have enough light, so it's worth treating as a shorter-lived, more frequently resown crop rather than expecting a single plant to last for months.
Pots, Compost, and Drainage
Whatever container you use, drainage holes are essential — herbs sitting in waterlogged compost will develop root rot within weeks. A good quality peat-free multi-purpose compost suits most herbs well. Avoid pots that are too large for the plant, since a big volume of compost around a small root system tends to stay wet for far too long after watering.
Watering Indoor Herbs
Overwatering is the single most common way indoor herb gardens fail. Most herbs prefer to dry out slightly between waterings rather than being kept constantly moist. Check the compost with a finger before watering, and only water when the top couple of centimetres feel dry. Always water at the base rather than over the foliage, and make sure any saucer beneath the pot isn't left holding standing water.
Feeding and Harvesting
Herbs grown in pots exhaust the available nutrients in their compost faster than herbs in open ground, so a diluted liquid feed every few weeks through the growing period keeps them productive. When harvesting, always pick from the top of the plant rather than stripping lower leaves, and take a little from several stems rather than cutting one stem right back — this encourages bushy, continuous growth rather than a single tired-looking spike.
Dealing With Common Problems
Yellowing lower leaves are often a sign of overwatering rather than a nutrient issue, so check the compost moisture before reaching for a feed. Leggy, stretched growth with pale leaves almost always points to insufficient light rather than anything wrong with the soil. Small flying insects around the compost surface are usually fungus gnats, a sign the compost is staying too wet, and are best solved by easing off watering and letting the top layer dry out more between sessions.
Rotating and Refreshing
Even with good care, herbs like basil and coriander are relatively short-lived and benefit from being resown every couple of months to keep a constant supply going, rather than expecting one plant to produce indefinitely. Keeping two or three pots at different stages of growth on the go at once is a simple way to make sure you're never left without fresh herbs to hand.