How to Keep Supermarket Herbs Alive for More Than a Week

Supermarket herb pots are grown fast, packed tight and sold to be used within days. Treated as houseplants they die in about a week, reliably, and everyone assumes they are personally bad at plants. They are not.

The actual problem

What looks like one healthy basil plant is usually twenty to thirty seedlings crammed into a pot meant for one. They are competing for the same tiny volume of soil and water, and they exhaust it fast. Nothing you do with a watering can will fix a root system that has nowhere to go.

Then harvest it properly

This is where most basil dies even after a good repotting. Do not pick individual leaves off the bottom. Cut whole stems just above a pair of small leaves, and the plant branches into two from that point. Picking leaves gives you a bald stalk; cutting stems gives you a bushier plant every time.

Herb by herb

• Basil hates cold. Never the fridge. A glass of water on the counter like cut flowers works well for a few days.
• Parsley, coriander, mint are tougher and quite happy in the fridge — stems in water, loose bag over the top.
• Rosemary, thyme, sage are woody and forgiving. They want less water than you think and will outlive everything else on the sill.

Cut herbs, not potted

Treat them like flowers. Trim the stem ends, into a glass with an inch of water, bag loosely over the top, in the fridge for everything except basil. Two weeks instead of three days.

When they finally go

Soft herbs freeze well chopped into an ice cube tray with a little oil or water. Not for salads afterwards, but perfect dropped straight into a pan.