Weekend work: Time to spray bindweed

Bindweed flourishes unchecked in the summer heat (Rex Features)

WHAT TO DO

* Although cultivated plants may flag in summer heat, bindweed (hereabouts called withy winder) flourishes unchecked, a ghastly indication of how deep its roots must be. August is a good month to spray this pernicious strangler with a herbicide based on glyphosate (Roundup).

* Dahlias are anxious to zoom into flower but should be disbudded until a good strong framework of leaf and stem has been built up.

* Check cordon tomatoes regularly and nip out side shoots growing in the axils between leaf and stem. Tie in the main stem frequently to its supporting cane. Watch out for new stems sprouting from the base of the plant. Sometimes they will grow almost as tall as the proper stem before you notice them. Watch out also for blight which can spread from potatoes to tomatoes. Fungicide can be used as a preventative, but not as a cure.

WHAT TO SEE

* The Plantasia festival at Kew runs until 7 September with barefoot walking trails, workshops focusing on herbal remedies and a chance (the first time in eight years) to climb to the top of Kew's pagoda, 50m off the ground. For more information call 020 8332 5655 or go to kew.org