Garden catnip

Garden catmint is fully hardy and survives winters in the lowlands of Germany, Austria and Switzerland outdoors without protection. Leave the dried shoots standing over winter; they protect the base and offer insects shelter. Cut back to ground level only from the end of March; after the first flowering you can shorten it by about a third, which often triggers a second flowering.

Garden catmint (Nepeta × faassenii) is a sterile hybrid (a cross of Nepeta racemosa × Nepeta nepetella) and does not form viable seed. Sowing is therefore ruled out. The most reliable ways to propagate it are two:

Division (simplest method): Dig up an established perennial in early spring (as soon as the first shoot tips are visible) or in early autumn. Divide the clump with a sharp spade into several pieces, so that each piece has its own roots and at least two to three shoots. Plant the pieces straight away in their new position and water in well. Older clumps benefit from division every three to four years, because otherwise the centre goes bare and flowering declines. Avoid dividing in summer heat.

Soft cuttings (for larger numbers): In late spring to early summer (roughly May to June), cut non-flowering shoot tips about five to seven centimetres long, just below a leaf node. Remove the lower leaves so that only two to three pairs of leaves remain at the top. Insert the cuttings into moist, lean seed compost and keep them evenly moist until roots have formed after about two to four weeks. Put the pots somewhere bright, but not in strong midday sun. In autumn of the same year the rooted young plants can go outdoors.