Monty wrote: “The best time to prune early-flowering clematis such as C.montana, armandii, alpina and macropetala, is immediately after they finish flowering.

“Obviously the timing will vary considerably in different parts of the country but the principle remains constant and for many of us this occurs at the end of May.”

It is important to prune these plants in May as next year’s flowers are formed on all the new growth made from this period until late summer.

This means if they’re pruned much later in the year, gardeners will be removing potential flowers that would bloom next spring.

Monty added: “Pruning of these clematis is solely to maintain their size and spread for your convenience rather than for any horticultural benefit.

“So cut back freely, not worrying about individual stems or the position of the cut.

“Then when you have finished, weed around the plant, water it well and mulch generously with garden compost or bark chippings.”

Pruning is extremely important, especially in May, as it can help to encourage new growth and help tidy up the look of the garden for summer.

It is also a time when bleeding after pruning or diseases are much less common because the frost has passed.

Lavender can be pruned at different times of the year, but depending on the variety, May is a great time.

There are a couple of popular varieties of lavender commonly grown in the UK, including English and French.

Both will need pruning, but the English variety tends to be more hardy, meaning it can be left outside throughout the year.

Pruning lavender plants will encourage better flowering and ensure they don’t become leggy and weak.

It is also recommended to prune hibiscus this month, pruning ahead of the new flowering season.

Established plants will require minimal pruning at this time of year, but young plants will need to be cut back hard.

When pruning hibiscus plants, they should be cut about a third of the way back, leaving at least two to three nodes on the branches for new growth.