Overwintering tender perennials

 Turning garden plants into houseplants

Geranium

I love a patio and yard filled with colorful plants and if I can get plants that I can use for more than one year so much the better. There are many plants that gardeners grow in their gardens and outdoor containers as annual plants that are actually perennial plants in warmer climates.  Some of our most common bedding plants that we treat as annuals fall into this category.  If gardeners rescue these plants before a frost, they can become attractive houseplants for the winter.

It’s also economical to keep a few tender perennials over the winter so you don’t have to buy them again in the spring. Many of these tender perennials can be multiplied by cuttings to produce a whole new selection to use outdoors next spring or to share with friends. Some tender perennials that are over-wintered become large, attractive plants that would be impossible to obtain with one summer’s growth.

There is a list of these tender perennials that can winter indoors given below. If these plants are growing in the ground, they should be dug up and carefully potted. If they are crammed into a container that is pretty full and lush it would be wise to separate the different plants and pot them separately. Check the plants and the pots carefully so you don’t bring in small surprise guests like frogs and mice.

Use a good, lightweight potting soil if you need to re-pot tender perennials you are bringing inside. Garden soil can bring in pests. You can use potting medium with fertilizer included but it isn’t necessary for most plants at this time of the year. Blooming plants do appreciate fertilization, however.

Some of these plants go semi-dormant in winter, even when brought inside.  They will begin growing again in the spring however, as the days lengthen.  The plants that do go into a resting stage can often be kept in a room that is well lit but has cool temperatures that stay just above freezing, such as a sunny porch.  Other tender perennials need room temperatures that don’t go below 55 degrees F. to do well over the winter.

Instead of bringing whole plants inside you can sometimes take cuttings of plants and over winter small plants you start from them.  It is better to start these plants outside in late summer, and then bring in the small pots before frost.  However, if frost threatens and it seems to be too much work to bring a large plant inside, take a few cuttings and try your luck.

 

List of tender perennials that can be brought inside for winter

Abutilon, often sold as container plants, make good houseplants.

Aloes, agaves, most are not hardy below zone 8, but can be overwintered inside.

Banana plants, will grow well in a sunny area inside.

Begonias, wax, tuberous, Rieger, angel wing, cane- all types of begonias will bloom all winter in the right conditions. Tuberous begonias and even cane types can be allowed to go dormant and the tubers stored. I always leave the tubers right in the pots and store them in a cool, above freezing place. Take the pots somewhere warmer and bright in February- March and let them start growing again.

Wax (fibrous rooted) begonias can make a pretty blooming plant all winter in bright light. Rieger types also do well inside as houseplants.  Rex types are great houseplants.

Brugmansia, most people bring these inside to a cool place just above freezing and let them go dormant in the pot. You can keep them growing and blooming in a warm, very sunny spot indoors.

Calla- you can bring inside and let them grow- or let them go dormant and store the bulbs in the pot until spring in an above freezing place.

Canna- canna will grow inside as foliage plants in bright light all winter or let them die back and save the rhizomes.

Coleus- bring the whole plant inside or take cuttings. If stems get woody and straggly looking cut them back.  Bright light is needed inside for good growth.

Colocasia, elephant’s ears- you can let them die back and store the bulbs or let them continue to grow as a houseplant if you have room.

Dipladenia and Mandeville can be overwintered but are a bit tricky.  They need bright light and warm conditions.

Eucalyptus, sometimes used in containers, grows well inside.

Fuchsia- plants will grow and bloom all winter in bright light. The smaller flowered varieties make better houseplants.

Gardenias- if you are below zone 7 bring these inside to save. They need cool, humid, sunny conditions inside.

Geraniums- you can store them in a semi-dormant phase in a cool, dark place or just pot them and let them bloom all winter in a warmer, brighter place. They will get quite large inside.

Gerbera daisies- will bloom off and on all winter if they are in bright light inside. I actually think gerbera do better inside than outside.

Gerbera daisy

Hibiscus-Tropical or Chinese - bring inside, in bright light they will bloom most of the winter. They’ll live many, many years and get very large.

Joseph’s coat (Alternathera ficoidea), good foliage plant.

Lantana, yep- it will grow and bloom all winter.

Lemon cypress needs the same conditions as rosemary, see below.

Lemon grass, needs bright light in winter.

Lemon verbena needs warmer, sunny conditions. It makes a small tree.

Lifesaver plant (Huernia zebrina), good houseplant.

Lipstick plant and goldfish plant, both make good houseplants.

Ornamental peppers- the smaller varieties with pretty foliage make the best houseplants.

Polka dot plants – keep pinched back so they don’t get leggy.

Rosemary- in zones 7 and lower rosemary should be overwintered inside. It needs cool, not above 65 degrees, sunny conditions for best survival. Most other herbs, including lavender, do not survive well inside over winter.

Setcreasea, the purple passion plant, grows well inside.

“Spikes” – dracaena – make good houseplants.

Sweet Bay- bring inside to overwinter.

Sweet potatoes will keep growing all winter in bright light and warm conditions.

Sweet potato with flower

Succulents-many of the new succulents are not winter hardy in zones 7 and lower. Bring them inside and they grow all winter. Check the hardiness zones of all succulents and sedums. If they are hardy in your zone it’s best to leave them outside.

Taro- let it grow through winter or let the leaves die back and save the tubers.

Bulbs that are tender for your zone can be allowed to die back and stored above freezing in net bags buried in shavings or just bring pots inside after potted bulbs have died back. All bulbs must be brought inside before a hard freeze. Bulbs include glads, dahlias, peacock lilies, rain lilies, crocosmia, pineapple lilies, (Eucomis) and other tender bulbs.

Don’t try to save too many tender perennials unless you have a big greenhouse. (Even I close my eyes and leave some behind.) Just save the most expensive, rarest or your personal favorites.  You can propagate cuttings from one or two plants for a new border of impatiens rather than trying to save the whole border. All plants need room and good light and the more you have, the more time you will spend caring for them.  Trust me, I know.