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Can I grow climbers through a shrub?

Q I have a pineapple guava in my garden. Please could you suggest a climber that would grow through it?

Ernest L. Jones, Chester, Cheshire

A Pineapple guava (Acca sellowiana) is an evergreen shrub with attractive foliage and unusual flowers.

While it is possible to grow climbers through shrubs, it is traditionally a deciduous climber through a deciduous host. If either party is evergreen, it may restrict light reaching the other’s foliage, causing bald patches or weak growth.

Also, two plants growing so close together will be competing for water and nutrients. It is best to let the host shrub have a few years’ start on the climber so that it is well established and able to take the weight of the climber.

Choose your climber very carefully so that its ultimate size does not overwhelm its host. In the right conditions pineapple guava can reach 10ft (3m) tall, but it will take a number of years to reach this size.

I would avoid roses as it will be difficult to keep them pruned, but there are many clematis to choose from. Suitable cultivars include ‘Barbara Jackman’, ‘Miss Bateman’, ‘Bees’ Jubilee’, ‘White Columbine’ and . Also worth considering are ‘Harlow Carr’, ‘Victor Hugo’,