Growing hydroponic herbs: a complete guide to year-round flavour
Basil, mint, cilantro, and parsley on a windowsill in January. Herbs are the crop that most changes how you cook.
Herbs are the highest-value crop you can grow at home. A supermarket packet costs a few dollars, wilts in days, and is always the wrong quantity. A single basil plant in a jar produces continuously for months and costs about a dollar to run.
| Herb | Harvest | pH | Notes |
|---|---|---|---|
| Basil | 2 to 4 weeks | 5.5 to 6.5 | The best hydroponic herb by a distance. Loves warmth and light. |
| Mint | 3 to 4 weeks | 5.5 to 6.5 | Vigorous to the point of nuisance. Always give it its own container. |
| Cilantro | 3 to 4 weeks | 5.5 to 6.7 | Prefers cool. Bolts above 75F (24C). |
| Parsley | 5 to 7 weeks | 5.5 to 6.5 | Slow to germinate, then extremely steady. |
| Chives | 4 to 6 weeks | 6.0 to 6.5 | Cut like grass and it regrows indefinitely. |
| Oregano and thyme | 6 to 8 weeks | 6.0 to 6.5 | Slower and woodier. Prefer a drier root zone, so drip suits them better. |
The pruning technique that matters
Most people harvest herbs wrongly, by picking individual large leaves off the bottom. That leaves a tall bare stem with a tuft on top, and the plant stops branching.
Instead, cut the stem just above a pair of leaves. The plant responds by pushing two new shoots from that junction. Do this from the moment the plant is about six inches tall and it doubles its branch count each time, giving you a dense bush instead of a spindly stick.
Keep basil from flowering
Once basil sets flower buds it diverts everything into seed and the leaves turn bitter. Pinch out flower buds the moment you see them and the plant carries on producing leaves for months longer.
Need a system to grow it in?
Every plan on this site is free and costs under $50 to build.