The lazy gardener's friend

Cosmos thrive on POOR soil. Rich compost gives you a forest of leaves and few flowers. In a tub, use a basic peat-free mix without added feed, and don't liquid-feed.

Water moderately; cosmos like to dry out slightly between waterings. Stake taller varieties with twiggy peasticks pushed in early — by August you can't get them in.

If a plant has gone all leaf and no flower, you're feeding it too well. Stop the feed, withhold water for a week, and it usually starts flowering within a fortnight.