Tuck up tender plants for winter
Protect frost-tender plants outdoors with our timely advice
Protect frost-tender plants with mulch, fleece and bubblewrap
Gardeners with a penchant for tender plants have been reasonably lucky for the past few years. A succession of mild winters have meant that most tender plants have sailed through the cold season unscathed. Yet there’s always the risk that frost and cold temperatures can bite when you least expect it.
1 KEEP ALPINES DRY
Growing at altitude in the wild, hardy alpine plants can shrug off frost and use a blanket of snow for insulation. Their real enemy in winter is heavy rain and boggy soil, which can make them rot. Ensure they’re planted in a well-drained gritty soil and use a vented plastic cloche or build a small perspex shelter supported on columns of bricks, so they can stay ventilated without getting their crowns wet.
2 LAY A MULCH
Adding a thick 10cm (4in) mulch around the bottom of a borderline hardy shrub, or over the top of a dormant tender perennial, can insulate the soil and keep its roots, tubers, bulbs or corms from freezing. Organic mulches (that will rot down in time) include bark, garden shreddings, compost, wellrotted manure, grass clippings, leafmould and straw. Try mulching with penstemons and semi-hardy fuschias...
3 Lift tender tubers
Plants such as dahlias, eucomis, begonias and gladioli have tender bulbs, tubers and corms that benefit from a deep mulch of compost topped with a layer of chipped bark in winter. In colder parts of the country it’s better to lift dahlias and cannas before the frosts, shaking off any soil, cutting off the stems to 10cm (4in) and leaving them to dry for a couple of weeks. Then, store them in a frost-free place in a suitable plastic tray filled with compost.
4 ADD A LAYER OF FLEECE
Tender plants, rooted cuttings and young autumn crops can all be protected from frost, wind and hail by swaddling them with horticultural-grade fleece. This lightweight, porous fabric allows plants to receive the light, warmth and moisture they need to grow, without making them overheat or increasing humidity. Hold it in place with heavy stones or bricks, but don’t drag the plant down. Make a tent over taller plants using garden canes and pegs or clips.
5 WRAP UP TENDER EXOTICS
Tender exotic plants such as banana plants and tree ferns will die if exposed to freezing temperatures, so if you can’t grow in pots and move them into a frost-free greenhouse or conservatory, it’s best to wrap them in a layer of fleece or hessian, with straw or polystyrene packed inside to protect their crowns. Aim to get this protective layer in place by late autumn. During any long periods of warmer weather, remove the ‘duvet’ to prevent the plant from ‘sweating’ and possibly rotting.
6 Protect patio pots with bubblewrap
Plants in containers are especially vulnerable to frost damage because their roots don’t enjoy as much insulation as they would if planted in the ground. Wrap the pots in a duvet of bubblewrap and hide it with a layer of hessian and twine for a more aesthetically pleasing look. Don’t forget that terracotta pots are porous, so ensure they stay well drained by setting them up on pot feet.