Frances Tophill's guide to May pruning

When the days are consistently warm, and the nights are warmer too, you can safely start to unwrap tender plants like tree ferns and bananas. Any damaged, rotting or slightly frost-damaged limbs and segments should be removed, clearing the way for a flush of new growth.

This is also classic ‘Chelsea chop’ season, which involves removing roughly a third of this year’s green growth from clumps of late-summer border perennials, to delay or extend their flowering period.

The shaggy growth of evergreen hedging like box, privet and euonymous can safely be trimmed, while frost-tender shrubs can be pruned with less risk of dieback.

• How to prune an evergreen hedge

More pruning advice for late spring:

• Arit Anderson's guide to May pruning
• Monty's May pruning clips
• Pruning mistakes to avoid

Plants to prune now:

This is a month to prune back plants that flowered earlier in the spring and to keep things neat so that summer growth doesn’t get out of hand, or feel overwhelming.

Japanese quince

Prune Chaenomeles now, to encourage flowers next spring and avoid a sprawling specimen.

Laurel

Cut back Prunus laurocerasus with hand shears or secateurs to avoid slicing through leaves – it's worth the effort, as damaged foliage will go brown.

Early-flowering clematis

Neaten up clematis once they’ve finished flowering to stop them overwhelming their location.

Penstemons

Trimming back penstemons encourages bushier growth that will stand up to wind, and smaller, more abundant but slightly later flowers.

Avoid pruning:

• Grapevines: To avoid excessive sap loss or ‘bleeding’, you should only prune these in the depths of winter. Fine out more about how to prune grapevines.
• Birch trees: These are similarly prone to bleeding if pruned now – although tapping the rising sap of (to drink) can be fun earlier in the year.
• Wisteria: This should be pruned in January and again in July. If you cut wisteria back now, you will interrupt its flowering.
• Hazel and other coppiced trees: Pruning hazel now that it is in leaf will result in weaker growth as you reduce the capacity for photosynthesis. Coppicing should be done in winter to promote strong stems.

Step-by-step: Pruning banana plants

The banana Musa basjoo is essentially a large herbaceous perennial that is slightly tender and slightly oversized – but don’t feel intimidated. Bananas stop producing new leaves in autumn, but as soon as the weather warms up they’ll sprout freely again, so it’s fine to cut off all the old ragged foliage and make a fresh start for this summer. Also remember that bananas readily regenerate from the ground, forming new suckers or offshoots. So if you do mess up, it will probably sprout new plants that can take over.

The main objective of pruning is to remove all the browned, unattractive growth and any rotting or frost-damaged parts now that the weather is warming up, so new growth can form from the healthy growing tip. You’ll need a pruning saw and gardening gloves, as this can get a little messy.

Step 1

Unwrap your banana from its winter protection once all risk of frost has passed. Then remove some of the plant’s own protective layers – the brown, dead sheathing.

Step 2

Squeeze the stem to find a point some way down where it feels firm and healthy. Cut the stem just below that point, at a gentle slant, using a pruning saw.

Step 3

Decide next whether you dare to be a little more drastic and remove even more of the stem. Doing this will bring the growing tip lower down, creating a shorter plant.

Step 4

By July, your banana will be lush, green and leafy, just like any other herbaceous perennial. What can seem drastic is often the best way to ensure healthy growth.

Also prune this way:

• Tree ferns such as dicksonia antarctica should also be unwrapped and pruned this month, after the last hard frost. Just snip off all of last year’s tatty old fronds individually 10-15cm from the point where they arise. Doing this means your tree fern’s trunk will grow taller – cutting the old fronds any shorter than 10cm will cause the trunk to narrow as it grows. Once pruned your fern will then unfurl a whole new set of beautiful fronds from the crown of the trunk.

Top Tip

Keeping the blades of your pruning tools clean and sharp is really important for the health of your plants, as it helps to avoid spreading pathogens. It’s vital for your own safety too, as blunt or clogged-up tools can cause injuries.

Plant resins and juices can be very sticky, especially in spring when sap is rising. So clean the blades of secateurs, loppers, saws and shears regularly using disinfectant, then apply lubricant to the blades and mechanisms with a cloth. But do take care not to cut yourself.