Weekend work: Time to prune berberis and trim box hedges

Most of the best topiary artists use hand shears rather than mechanical trimmers (Rex Features)

WHAT TO DO

* Where berberis is grown freely as a shrub, it does not need regular pruning, though old evergreen specimens can be rejuvenated by cutting out some of the old stems at ground level. This will persuade the thing to throw some vigorous new shoots.

* This month or next is the best time to trim box hedges. Topiary needs a careful eye. Most of the best topiary artists use hand shears rather than mechanical trimmers. Holly makes more uncomfortable topiary, but as with box, it should be clipped to shape this month.

* Established hedges of beech should be trimmed now. If you do not have a good eye for a straight line, stretch a string along the hedge to give you a guide.

* As soon as bushes of santolina (cotton lavender) have finished flowering, cut hard back to encourage new growth from the base. Lavender is loath to sprout from old wood, but santolina does and will look much better next year if you give it harsh treatment now.

WHAT TO SEE

* Visit Andrew Bliss's transformation of concrete screed into jungle at 87 St John's Rd, London E17. Raised borders, decking, slate walls, water features, and sculpture – all in a plot of 15ft x 25ft. Today, 1-5pm, £3.