How to protect tender plants over winter
Bring a taste of the tropics to your garden
Many of us love the taste of the tropics when it comes to our gardens but unfortunately the downside is that these plants have to be protected from the frost over winter. The level of protection is dependant upon whereabouts in the UK you live, what would have to be protected in Scotland may be perfectly fine left out in the garden on the south coast.
Plants needing protection are the exotic flamboyant tropicals such as cannas and ginger, succulents like aeoniums, echeverias and aloes, perennial bedding; geraniums, fuchsias, tree ferns, citrus, some shrubs, tubers, some bulbs, some palms and don’t forget any vegetable crops still in the garden.
Tip: Don’t prune shrubs towards the end of autumn as they are still capable of putting on some new growth which will get killed by frost.
Prepare the greenhouse
- Clean out and scrub down the paths and staging with a mild Jeyes fluid solution; allow to dry before bringing in the plants.
- Attach bubble wrap to form a tent inside the greenhouse; this cuts down on heating bills.
- Make sure your greenhouse heating is in working order and safe.
- Root vegetables such as carrots, parsnips, turnips and swede still in the ground can easily be protected by a thick mulch of straw and harvested all winter.
- Green leafy vegetables can be protected by covering with horticultural fleece or even an old net curtain can keep off a light frost.
- Brussels sprouts should not need covering they are able to cope with a frost.
Perennial summer bedding
- Move to the windowsill in the spare bedroom and just give a little water when the compost has dried out.
- Place in the greenhouse or a porch but make sure it doesn’t get below freezing.
- Tip: Tender bedding geraniums can be grown indoors on a sunny south facing windowsill, just water sparingly and give a weak solution of tomato food every week over winter. I’ve had some in flower continually for 3 years on a warm sunny south facing windowsill.
Tender tropicals, ferns and shrubs
- If planted in the garden dig carefully around the root-ball, lift and place in a container with some fresh compost.
- Bring into the greenhouse and only give a little water when the compost has dried out.
- Make sure the very tender plants are planted in containers which can be moved into shelter.
- If they are too large to be brought indoors wrap up with sacking or 2 – 3 layers of horticultural fleece on the days frost is forecast.
- When it comes to tree ferns it is only the very top which needs protecting and again don’t just put a plastic bin liner over the crown. Pack around the top with straw or sheep’s wool and secure on with sacking, horticultural fleece or an old pillow-case.
Semi-tender shrubs and perennials
- If planted in a container use a loam based compost which drains freely.
- If the pot is too heavy to be moved stand it on some pot feet or bricks so that the water can drain away.
- Terracotta pots easily crack with the frost so need to be protected. Wrap just the container in bubble wrap, sacking or plastic bin liners stuffed with roof insulation, shredded paper or straw.
- Don’t cover the plant in plastic instead use sacking or 2 – 3 layers of horticultural fleece. If you use bubble wrap on the plants they can ‘sweat’ over the winter which will rot the crown. Bubble wrap can be used for only a couple of days and as soon as the temperature comes above freezing it must be removed.
- Tender perennials planted in the garden can be cut down then covered with a thick layer of mulch.
- If you only have a small isolated perennial which needs some protection, such as Verbena bonariensis, pack an old wire hanging basket with straw or sheep’s wool then place upside down over the crown and peg down.
Tender bulbs and tubers
- Once the tops have died off lift and brush off as much compost as possible.
- Spread out on some newspaper to dry off.
- Bulbs can be stored somewhere frost free; once they have dried off.
- Tip: The nets off oranges come in handy; they can be hung from the roof in the shed to avoid the bulbs being eaten by mice and also to ensure a good airflow around the bulbs which is essential to prevent them rotting.
- Dahlia tubers can be stored in barely damp compost, sawdust or Perlite.
Although protecting tender plants seems like a lot of trouble, they are well worth the effort; giving your garden the touch of the tropical and saving money by not continually buying new tender bedding plants.