Weekend Work: Time to sow cobaea

What to do

There is certainly a fuzz of green on the branches in the hedgerows that shows something is on the move. Perhaps it is not too soon to cut back penstemons, which look very weatherbeaten after winter. New buds are also breaking at the base of Artemisia 'Powis Castle'. This is the sign you should wait for before cutting the stems hard back. In the north, this might not be until April.

Last year I sowed the magnificent climber, cobaea, on 25 March and made a note subsequently that sowing could have been a week earlier. So, for me, that is today's job. Set the seeds on edge, pushing each one into a small pot of compost. Wrapping each individual pot in clingfilm until the seeds emerge keeps the compost damp without further watering. Germination can take up to a month. Cobaea, which has stiff fleshy bell flowers of purple, flourishes in long, late autumns such as the one we had last year.

]Outdoor peaches and nectarines are just coming into flower. If you feel that there are too few insects on the wing to pollinate the flowers, do it yourself. Rabbits' tails used to be much favoured for this job and there is a wretched rabbit raiding the parsley whose tail I wouldn't mind using. But a paintbrush does just as well.

]It is extraordinary how, at the slightest burst of warmth, crocuses start turning themselves inside out to sunbathe. Even early flowers of 'Tulipa clusiana' will fling themselves flat in abandon. It's a wonderful sight, when it happens. Unfortunately, weeds start to flourish now too, especially goosegrass. Bittercress is even worse, spitting out a thousand seeds from each capsule. Pull them up quick.

What to see

The London Orchid Show runs today and tomorrow (10am-5pm) at the RHS Lawrence Hall, just off Vincent Square, London SW1. As well as hundreds of the real things, there's an exhibition of some of the best paintings of orchids ever made, part of the unrivalled collection built up over the years by the Lindley Library. Tickets are £5. For more information call 0845 612 1253 or go to rhs.org.uk/londonshows