In the UK, herbs considered tender might include:
These herbs are all best treated as annuals in the UK, and need to be kept frost-free. They can all be grown from seed: follow the instructions on the seed packet, remembering that these plants require warm conditions to grow, so are best germinated on a windowsill or in a heated propagator. Rocket is the least fussy of these to grow, being almost frost hardy, and will happily germinate in an unheated greenhouse from spring onwards.
Tip: When growing from seed, we recommend using modules or plug trays as this minimises root disturbance when potting on.
If you like a shortcut, try buying supermarket pots of basil, which contain many seedlings, and pot them on individually. Lemongrass stalks can often be bought in a similar way – separate them and grow individually. Both enjoy hot surroundings, so keep indoors or in a greenhouse until all danger of frost has passed. After that, basil is often grown alongside tomatoes in the greenhouse, but, it is equally happy in a sunny spot outside such as in a container on the patio.
Coriander is trickier to grow, simply because it responds to stress by flowering. Try and make sure seedlings don't get pot bound, overly dry or short of nutrients, and try to keep root disturbance to a minimum – for this reason, separating supermarket pots of coriander seedlings tends to be less successful. On the plus side, both the flowers and seeds of coriander are edible.
Keep picking leaves of coriander, rocket and basil to encourage new growth and pinch out growing tips to discourage flowering, which can make the leaves tough.
Words & images: Ruth Ridley