Coleus perennial or annual

Winter Care Tips For Your Coleus

A coleus plant is hardy, able to survive in both a container indoors and in the soil outside. However, being a warm weather loving plant, it will not survive a harsh, cold winter. When the weather begins to turn cold you will need to take some precautions to ensure a healthy coleus in the spring.

Step 1 – Bring It Indoors

For starters if you have your plants outside, then transplanting indoors will save your plants from freezing. Carefully dig around the plant and lift out of the soil. Transplant it into a pot with soil that is already moist.

Step 2 – Cut It Back

When the weather begins to drop, especially at night, cutting back the coleus flowers will help the plant conserve a lot of energy and food. You do not have to worry about hurting the plant too much if you cut it back too far. Coleus is a very hardy plant and can handle the cutting. In fact, it will come back even bushier and more colorful than before.

Step 3 – Cover At Night

If you live in an area that does not get below 50 or even 45 degrees in the winter time, then you will only need to place a small covering over them to keep the chill off the flowers and leaves. Remove the covering in the morning and let it get full sun.

Overwintering coleus is easy, and it’s a great way to keep your favorite varieties year after year. In this post, I’ll show you how to keep coleus over the winter, and give you tons of coleus care tips too.

Coleus plants are one of the most colorful plants you can grow in the garden, and they add a wonderful tropical feel. They come in all kinds of color combinations too.

One of the things I love the most about them is that they add tons of color to shady gardens and planters. Once you know how to grow coleus in winter, you can keep that beautiful color year after year!

Are Coleus Plants Annuals Or Perennials?

Even though you’re likely to find coleus plants for sale as annuals in most areas of the country, it’s actually a tender perennial that can survive for many years in the right climate.

Coleus temperature tolerance isn’t very high, and they can’t handle the cold (coleus cold hardiness is zone 10 or warmer). The plants will start to die at the first touch of frost in the fall.

But don’t worry, overwintering coleus indoors is pretty easy, and there are a few ways you can do it. That means you can grow your favorite coleus plant varieties year after year without spending a dime buying new plants each spring.

Growing coleus in containers outdoors

Methods For Overwintering Coleus

There are two ways you can overwinter your favorite coleus varieties indoors. You can use these same methods for any type of coleus plant you’re growing in containers or in your garden…

  1. Potted coleus plants can be brought indoors and grown as a houseplant.
  2. You can take cuttings from your plants, and root them for growing indoors.

How To Overwinter Coleus Indoors

Below I will describe both of these methods in detail. If you’ve never tried overwintering coleus before, I encourage you to experiment with both methods and see which one works best for you. Then after that, I will give you tips for how to take care of a coleus plant indoors in winter.

Growing Coleus Houseplants

If you’re growing coleus in pots, you could overwinter them as houseplants by bringing the whole container inside for the winter. If your potted coleus has grown huge over the summer, you can trim it back so it’s a more manageable size for growing indoors (be sure to keep the cuttings so you can try the second method too!).

Keep in mind that your coleus plant is used to growing outside all summer. So, the plant may droop or even drop a few leaves after bringing them indoors. That’s completely normal behavior, and it should pop back in a few days.

Coleus plant indoors for winter

Growing Coleus Cuttings In Water

Rather than overwintering coleus plants in containers, sometimes it’s less work to take cuttings instead. This is also a great way to keep the varieties you grew in the garden. Coleus root in water, and can be potted up and grown as a houseplant too.

It’s best to take coleus cuttings before it starts to get cold outside, and you’ll definitely need to do it before frost damages the plant. Once they start to die back from the cold, the cuttings may not take root.

Growing coleus in water

Bringing Coleus In For The Winter

However you decide to try overwintering coleus, it’s important to debug them before bringing them indoors. If you plan to bring the whole plant inside, then follow these instructions for debugging potted plants.

You can debug your cuttings using the same method, or you can do it on a smaller scale inside. Soaking the cuttings in the sink for about 10 minutes will drown any pests insect that are on the leaves. Be sure to weigh the cuttings down so they won’t float (I used a dinner plate).

Soak cuttings in water to kill coleus pests

You can add a squirt of mild liquid soap to the water to help kill pest insects. After they are done soaking, rinse the leaves with plain water to remove any bugs, dirt and soap. Once you’re done, simply place the cuttings into a vase of water to root them.

When the cuttings have grown some nice healthy roots, then you can pot them up into a container. You don’t need to buy any special soil for transplanting coleus cuttings, you can just use a general purpose potting soil to pot them up.

Washing coleus leaves to kill bugs

Tips For Coleus Plant Care Indoors

Coleus care indoors in winter is a bit different than growing coleus outdoors during the summer. Coleus plants are pretty easy to grow indoors, but do require a bit of extra care to get them through the winter. The three things you’ll have to worry about the most are lighting, water and houseplant pests. Here are some quick coleus winter care tips to help you out…

Coleus Houseplant Light Requirements

Though they prefer the shade outside, coleus plants will grow their best indoors with lots of light. Place the pot in a sunny window where it will get plenty of bright, indirect sunlight. If you don’t have much natural light in your home, then you can add a grow light to keep them from getting leggy and reaching for the light. Plug it into an outlet timer to give your plant plenty of light even when you’re not home.

How Often To Water Coleus Plants Indoors

Keep the soil evenly moist through the winter, but never soggy. Allow the soil to dry out a bit on top before watering your plant again. To avoid overwatering, stick your finger one inch into the soil to make sure it’s not wet. If you struggle with watering houseplants, then you can get yourself an inexpensive soil moisture gauge to help you get it perfect every time.

Growing coleus indoors over the winter

Controlling Indoor Coleus Pests

One of the biggest challenges of overwintering coleus indoors is controlling houseplant pests. In my experience, coleus are very prone to being infested by pests like aphids and spider mites. Potted plants can also have issues with fungus gnats (they don’t eat the leaves though). Be sure to check your plants regularly for signs of infestation.

To help control any bugs that might show up, you could spray your coleus with a neem oil solution. Neem oil is an organic product that makes it much easier to get rid of bugs on houseplants, and can even prevent infestations. Read more about how to use neem oil insecticide here.

You could also use a solution of soapy water and spray it on the leaves of the infested houseplant (I use 1 tsp of mild liquid soap per 1 liter of water). If you don’t want to make your own, you can buy organic insecticidal soap instead.

If your plant is small enough, bring it to the sink or shower and wash the leaves with this soap and water solution. Keep in mind that sprays can damage plants. So it’s best to test any type of spray on a few leaves before treating the entire plant.

Overwintering coleus indoors takes a bit of work, but it’s worth the effort to keep your favorite varieties. It’s easy to bring them indoors as cuttings or grow them as houseplants until spring. Now that you know how to care for a coleus plant indoors over winter, you can grow them year after year (and save yourself money every spring!)

If you like the idea of rooting cuttings in water to create new plants, then you will love my Plant Propagation eBook. It will teach all of the techniques you need to get started propagating all of your favorite plants right away!

Related Products

Recommended Books

  • Hot Plants for Cool Climates
  • Winter Houseplant Care
  • Houseplant Pest Control
  • Plant Propagation Made Easy!

More Posts About Overwintering Plants

  • How To Overwinter Sweet Potato Vines Indoors
  • How To Overwinter Pepper Plants Indoors
  • How To Overwinter Brugmansia Plants Indoors
  • Overwintering Tropical Plants Indoors

Share your tips for overwintering coleus plants or cuttings in the comments below.

Henna Coleus foliage

Henna Coleus foliage

(Photo courtesy of NetPS Plant Finder)

Henna Coleus

Henna Coleus

(Photo courtesy of NetPS Plant Finder)

Height: 28 inches

Spacing: 12 inches

Sunlight:

Hardiness Zone: (annual)

Brand: Ball

Ornamental Features

Henna Coleus’ attractive crinkled pointy leaves emerge chartreuse in spring, turning coppery-bronze in color with showy buttery yellow variegation and tinges of coral-pink the rest of the year. Neither the flowers nor the fruit are ornamentally significant.

Landscape Attributes

Henna Coleus is an herbaceous annual with an upright spreading habit of growth. Its relatively coarse texture can be used to stand it apart from other garden plants with finer foliage.

This is a relatively low maintenance plant. The flowers of this plant may actually detract from its ornamental features, so they can be removed as they appear. Deer don’t particularly care for this plant and will usually leave it alone in favor of tastier treats. It has no significant negative characteristics.

Henna Coleus is recommended for the following landscape applications;

  • Mass Planting
  • Border Edging
  • General Garden Use
  • Container Planting
  • Hanging Baskets

Planting & Growing

Henna Coleus will grow to be about 28 inches tall at maturity, with a spread of 16 inches. When grown in masses or used as a bedding plant, individual plants should be spaced approximately 12 inches apart. Although it’s not a true annual, this fast-growing plant can be expected to behave as an annual in our climate if left outdoors over the winter, usually needing replacement the following year. As such, gardeners should take into consideration that it will perform differently than it would in its native habitat.

This plant does best in partial shade to shade. It requires an evenly moist well-drained soil for optimal growth, but will die in standing water. It is not particular as to soil pH, but grows best in rich soils. It is highly tolerant of urban pollution and will even thrive in inner city environments. Consider applying a thick mulch around the root zone over the growing season to conserve soil moisture. This is a selected variety of a species not originally from North America. It can be propagated by cuttings; however, as a cultivated variety, be aware that it may be subject to certain restrictions or prohibitions on propagation.

Henna Coleus is a fine choice for the garden, but it is also a good selection for planting in outdoor containers and hanging baskets. With its upright habit of growth, it is best suited for use as a ‘thriller’ in the ‘spiller-thriller-filler’ container combination; plant it near the center of the pot, surrounded by smaller plants and those that spill over the edges. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.

Coleus Care – Information On Growing Coleus

Perhaps you know them as painted nettle or poor man’s croton, depending on where you’re located, but for many of us we simply know them as coleus plants (Coleus blumei). I, for one, love them, as do many others. They have some of the most stunningly colored foliage—in combinations of green, yellow, pink, red, maroon, etc. Coleus also have a wide variety of leaf sizes and overall shapes. This means that no matter what area you are looking to put coleus, you can find one that will be perfect. These plants are great for adding color in the garden (or home), especially in those dark, drab-looking corners.

Growing Coleus Plants

Coleus is probably one of the easiest plants to grow and propagate. In fact, the plants root so easily that you can even start cuttings in a glass of water. They can also be propagated by seed indoors about 8-10 weeks prior to your last expected spring frost.

Coleus can be added to beds and borders for interest or grown in containers. They need fertile, well-draining soil and usually perform best in areas with partial shade, though many varieties can also tolerate sun.

When growing coleus, keep in mind that these beauties can grow rapidly. Plant coleus close together as bedding plants or tuck them into baskets and containers for a fast growing and spectacular addition.

Care for Coleus Plant

Caring for coleus is just as easy. They need to be kept moist, especially newly planted coleus. Container plants also require more frequent watering than those grown in the garden. Although it’s not required, the plants can be given a boost of half-strength liquid fertilizer during their active growth in spring and summer.

Their spiked flowers usually appear in summer; however, these can be removed if desired. You can also pinch the shoots of young coleus plants to produce bushier growth.

Another factor in coleus care is overwintering, as these plants, which are considered tender annuals, are highly susceptible to cold temperatures. Therefore, they must either be dug up, potted, and brought indoors for overwintering or grown through cuttings to establish additional plants.

Winterizing Coleus: How To Overwinter Coleus

Unless you take precautions beforehand, that first bout of cold weather or frost will quickly kill off your coleus plants. Therefore, winterizing coleus is important.

Wintering a Coleus Plant

Overwintering coleus plants is actually quite easy. They can be dug up and overwintered indoors, or you can take cuttings from your healthy plants to make additional stock for next season’s garden.

How to Keep Coleus Through Winter

Given adequate light, coleus overwinters easily indoors. Dig up healthy plants in the fall, just before cold weather hits. Make sure you get as much of the root system as possible. Pot your plants in suitable containers with well-draining soil and water them thoroughly. It may also help to trim back the top half of growth to reduce shock, though this is not required.

Allow your plants to acclimate for about a week or so prior to moving them inside. Then place the newly potted plants in a sunny location, such as a south- or southeast-facing window, and water only as needed. If desired, you can include half-strength fertilizer once a month with your regular watering regimen. You may also want to keep new growth pinched to maintain a bushier appearance.

In spring you can replant the coleus back in the garden.

How to Overwinter Coleus Cuttings

Alternatively, you can learn how to keep coleus through winter by taking cuttings. Simply root three- to four-inch (7-13 cm.) cuttings prior to cold weather by potting them up and moving them indoors.

Remove the bottom leaves of each cutting and insert the cut ends into damp potting soil, peat moss, or sand. If desired, you can dip the ends in rooting hormone, but you don’t have to since coleus plants root readily. Keep them moist in bright, indirect light for about six weeks, at which time they should have enough root growth for transplanting to larger pots. Likewise, you can keep them in the same pots. Either way, move them to a brighter location, such as a sunny window.

Note: You can even root coleus in water and then pot up the plants once rooted. Move the plants outdoors once the warmer spring weather returns.

Grow coleus in winter? It can be done!

Can’t bear to part with your favorite coleus when fall frost looms? You don’t have to! Coleus (Solenostemon species) are among the easiest plants in the world to root from cuttings, and getting them to overwinter indoors is almost as simple.

Here’s how:

Step 1: Six weeks before your first autumn frost, take four-inch-long tip cuttings from your favorite coleus. Strip the leaves from the bottom two inches of each cutting. Stick the bare portion of each stem into a small pot of sterilized potting soil (1 cup of soil should do). Make sure you have at least one leaf node buried in the soil. Keep the potting mix damp but not soggy, place the cuttings in bright light but out of direct sun, and you should have well-rooted plants within four weeks. If not, try again. (While it’s true you can root coleus cuttings in a glass of water, the roots are fragile and easily injured when you pot up your plants. It’s so much easier to start with the roots in good soil.)

Step 2: Once your cuttings are well-rooted, pot them up into pots that hold two to three cups of soil. Move them to the sunniest window of your house (or set them up under artificial lights for the winter). Make sure the plants remain at temperatures above 60 degrees F. for the entire winter. Coleus hate to be cold!

Step 3: Once your plants are settled on their windowsills, add a half-strength dose of timed-release fertilizer to the soil surface of each pot. (Read the package label for recommended dosage — no guessing allowed!) Pinch the growing point out of each tip to produce stronger, bushier plants.

Step 4: This is very important — don’t love your plants to death! Coleus should be kept rather dry over the winter to avoid rotting their roots. Remember, these are tropical plants that prefer sun and heat. They don’t take kindly to cold, wet soil, so water only when the pot seems fairly light and the soil surface is completely dry. (You’ll get the hang of it with a little practice.)

Step 5: The low light levels of mid-to-late winter are tough on coleus. They long for the tropics, where the sun shines 12 hours a day. If your plants are yearning, pleading, begging for more light (you’ll know by the way they lean toward the sun on weak, spindly stems and give off small, pitiful whimpers whenever you enter the room), consider investing in inexpensive grow lights to supplement your natural light.

A special note: Due to changes in light level, coleus sometimes alter their leaf colors in winter. The new shades can be less than dazzling (OK, I admit it, they can be rather murky!). They may look nothing like the beautiful plants you remember from the garden. Don’t throw them away! They will recover their vivacious personalities once they see some serious sunlight. (Would this be a good time to mention that, for obvious reasons, you might want to label your plants when you take the cuttings?)

Step 6: You’ve made it through winter. Now what? Acclimating indoor plants to the outdoors is best done in stages. Start by placing your coleus in bright shade on days when temperatures are above sixty degrees. Bring them back in at night if temperatures drop below 55 degrees F. Gradually ease the plants into more sun, making sure to keep up with their increasing water needs. Don’t drown them, though. Indoor plants often wilt to protect themselves from sun that’s stronger than they’re used to. If the root-ball is well-watered, then the plants need less sun, not more water.

Step 7: You’ve loved, sheltered, and tended your babies all winter long, and you’re dying to get them into the garden. Are they finally ready for planting? Tropical plants like coleus should be placed in the garden once night temperatures are sure to remain above 50 degrees. Don’t rush to plant sooner. You’ll only risk damage to their tender little leaves. Once the weather’s warm, they’ll grow like crazy and you can be proud you grew them yourself!

Copyright 2008 Pam Baggett, author of “Tropicalismo! Spice Up Your Garden With Cannas, Bananas, and 93 Other Eye-Catching Tropical Plants” (Timber Press, October 2008).

How to overwinter tender perennials

Tender perennials, such as pelargoniums, fuchsias, osteospermums and marguerites look great all summer, but unless they are given protection from the harsh winter weather, they will need to be replaced each spring. If you can do this, they will last for years, indeed many will put on even better display in their second and third years. If you have limited space for overwintering plants, make it a priority to save those which are expensive to buy, such as pelargoniums and standard fuchsias, as well as anything unusual that might be difficult to find the following spring. After that, choose favourite plants and flower colours so you can continually improve your summer border displays year on year. There are a range of techniques on how to overwinter tender perennials,which will depend largely on the plants themselves.

Here’s my plant-by-plant survival guide:

Agastache ‘Blue Fortune’

In mild gardens they can be overwintered outside if you protect the roots with piles of dry leaves, composted bark or straw. If you want the whole plant to survive, overwinter it somewhere the temperature doesn’t fall below 5°C. Pot it up individually and place it on a windowsill of a cool room, or place it under the staging in a heated conservatory or greenhouse.

Arctotis x hybrida

These fiery African daisies produce flowers from July to September and make long-lasting container plants for a sunny patio or courtyard garden. They are very tender and prone to basal rotting in winter so need to be kept somewhere the temperature doesn’t fall below 5°C – use a max/min thermometer to keep track. They can either be potted up individually and placed on a windowsill of a cool room, or placed in a well-lit, but shaded position in a heated conservatory or greenhouse.

Argyranthemum (marguerite)

Marguerites can be overwintered in several ways, but they must be kept frost free, Ideally, don’t allow the temperature fall below 5°C. You can keep one or two flowering all winter by placing them in a heated greenhouse or conservatory. Otherwise, they can either be potted up individually and placed on the windowsill of a cool room, or placed under the staging in a heated conservatory or greenhouse. Alternatively, you can save space by packing several plants into tray. Lift the plants and cut back the stems before placing them in a crate topped up with just-moist compost. I successfully overwinter standards by trimming back this year’s growth by about one-third and keep plants ticking over during the winter by placing them in a greenhouse with a minimum temperature of 5°C. You can also take cuttings now as insurance, kept at a minimum temperature of 7°C.

Begonia

Tuberous begonias are best lifted before the first frost and cut back to 10cm. The stems will dry and naturally fall from the tubers, which can then be boxed up in just-moist compost and placed somewhere the temperature doesn’t fall below 5°C. Fibrous-rooted begonias are best overwintered as ‘dormant’ plants. Pot them up individually, cut back to 15cm and place on a windowsill of a cool room, or under the staging in a heated conservatory or greenhouse with a minimum temperature 5°C. You can also take cuttings now as insurance and keep them at a minimum temperature of 7°C.

Brachyscome multifida

This slightly tender perennial with pretty flowers and finely divided foliage can also be overwintered successfully somewhere the temperature doesn’t fall below 5°C. Before the temperatures get too low in early autumn, either pot-up plants individually and place them on the windowsill of a cool room, or under the staging in a heated conservatory or greenhouse. In milder areas you might get away with overwintering plants in a well-insulated coldframe or greenhouse. You can also take cuttings now as insurance if they are kept at a minimum temperature of 7°C.

Calceolaria integrifolia (slipper flower)

If your soil is not too cold or wet in winter, calceolarias will survive outside in a sunny, sheltered spot. Cut back the top growth to 15cm and protect the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants in early spring when the worst of the frosts are over. Elsewhere, cut back hard after lifting and store in crates of just-moist compost placed somewhere cool, well-lit and frost free. You can also take cuttings now as insurance if they are kept at a minimum temperature of 7°C.

Canna (Indian shot)

In mild areas with free-draining soil, Indian shot plants can be left to overwinter in the ground, but in colder regions these half-hardy perennials need to be lifted and stored to protect them from the worst winter weather. Do this as soon as the first frosts have burnt the leaves black, then cut back the top-growth to 15cm and lift the plants from the ground. Clean off as much soil as possible before trimming any straggly, fine roots. Store them in boxes of dry compost to overwinter them in the garage, although any cool but frost-free place would do. The tubers are replanted in the spring once the danger of frosts has passed.

Cineraria maritima

This nearly hardy grey-leaved plant will survive outside in mild, sheltered gardens with well-drained soil if the winter isn’t too bad. It will then flower in its second year and grow into a substantial plant. You can prevent it getting leggy by cutting back the top growth to 15cm and protecting the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants in early spring when the worst of the frosts are over. In really cold gardens, overwinter by placing it in a coldframe or under the staging in an unheated greenhouse.

Coleus

You either love or hate these colourful foliage plants. They are very easy to raise from seeds or cuttings and can be overwintered successfully if kept where the temperature doesn’t fall below 5°C. Either pot them up individually and place on the windowsill of a cool room, or cut back foliage to 15cm and keep under the staging in a heated conservatory or greenhouse.

Cosmos atrosanguineus (chocolate cosmos)

If the soil is not too cold or wet in winter leave in the ground where they have been growing. Cut back the top growth to 10cm and protect the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants during early spring when the worst of the frosts are over. In colder areas, after the foliage has died back in autumn, reduce the stems to within 5cm of the roots. Lay in a tray of soil or compost and over-winter in a frost-free environment until early spring. Bear in mind new growth does not appear until late spring, so don’t be in a hurry to throw away plants that haven’t sprouted.

Dahlia

Traditional advice dictates that you have to lift dahlias each autumn, but these days less severe winters mean that dahlias can be left to overwinter in the ground in mild areas provided you have free-draining soil. If you have heavy clay, lift these half-hardy perennials and store them to protect them from the worst winter weather as soon as the first frosts have burnt the leaves black. Cut back the top-growth to 15cm and lift the plants from the ground. As much soil as possible should be cleaned off, before trimming any straggly, fine roots. Store them in paper bags or boxes of shredded newspaper or dry compost to overwinter them in the garage, although any cool but frost-free place would do. The tubers are replanted in the spring once the danger of frosts has passed.

Datura (Brugmansia suaveolens)

These stunning trumpet flowers are pretty tough and respond well to being cut back hard. In mild gardens they can be overwintered outside if you protect the roots with piles of dry leaves, composted bark or straw. If you want the whole plant to survive, overwinter it somewhere the temperature doesn’t fall below 5°C. Either pot-up individually and place on the windowsill of a cool room, or place under the staging in a heated conservatory or greenhouse.

Diascia

Overwintered plants often put on a better display than new plants, so if your soil is not too cold or wet in winter leave diascias in the ground where they have been growing. Cut back the top growth to 15cm and protect the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants during early spring when the worst of the frosts are over. Elsewhere, keep them somewhere the temperature doesn’t fall below 5°C. Such tender plants can either be potted up individually and placed on a windowsill of a cool room, or kept under the staging in a heated conservatory or greenhouse. You can also take cuttings now as insurance, kept at a minimum temperature of 7°C.

Felicia

Felicias are tougher than they look and can be overwintered successfully outside in mild areas provided the soil is not too wet. Variegated varieties are less hardy and so are best overwintered somewhere the temperature doesn’t fall below 5°C. All felicias can be kept flowering throughout the winter if you have heated greenhouse or conservatory. In this case, pot up individual plants, trim them lightly and water before placing on a windowsill of a cool room. Lightly trim overwintered plants again during late spring to tidy them up and encourage bushy growth, before planting outside. You can also take cuttings now as insurance kept at a minimum temperature of 7°C.

Fuchsia

Although hardy varieties can be left outside to overwinter, the top growth is likely to be cut back by frosts. So unless you garden in a mild area, it’s worth trimming it in autumn and laying the trimmings over the crown to provide an insulating layer against severe frost. Tender fuchsias can be overwintered outdoors, too, in mild areas, provided the soil is not too cold or wet. Cut back the top growth to 15cm and protect the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants during early spring when the worst of the frosts are over. Elsewhere, they need to be kept somewhere the temperature doesn’t fall below 5°C. Trim back the top growth by about half and pot up individually before placing on the windowsill of a cool room, or in a heated conservatory or greenhouse. You should be able to successfully overwinter standard fuchsias by trimming back this year’s growth by about one-third and keeping plants ticking over during the winter by placing them in a greenhouse with a minimum temperature 5°C.

Gazania

These are very tender plants that can’t cope with winter cold or wet, so they need to be kept somewhere the temperature doesn’t fall below 7°C. Such tender plants can either be potted up individually and placed on the windowsill of a cool room, or placed under the staging in a heated conservatory or greenhouse. You can also take cuttings now as insurance kept at a minimum temperature of 7°C.

Glechoma hederacea ‘Variegata’

A wonderful trailing plant that can be successfully overwintered by cutting hard back and keeping somewhere the temperature doesn’t fall below 0°C. Pot-up individually and either place on a windowsill of a cool room, or under the staging in a heated conservatory or greenhouse. New growth put on in spring can be used for taking cuttings. You can also take cuttings now as insurance – keep them at a minimum temperature of 7°C.

Helichrysum petiolare

This attractive foliage plant doesn’t do as well in its second year, so it is only worth overwintering them if you want cutting material in spring. The best way to achieve this is to cut back the plants to 15cm and pot them up individually before placing them on a windowsill of a cool room, or under the staging in a heated conservatory or greenhouse. Maintain a temperature of at least 5°C. During early spring water sparingly and provide a little heat to encourage new shoots that will make excellent cutting material. You can also take cuttings now as insurance kept at a minimum temperature of 7°C.

Impatiens

Plants that are in good condition and free of pests and diseases can be overwintered successfully. If you can maintain a temperature of 13°C you can keep them flowering all winter. Otherwise, a temperature above 7°C will see them through. Pot them up individually and either place them on a windowsill in a cool room, or under the staging in a heated conservatory or greenhouse. You can also take cuttings now as insurance kept at a minimum temperature of 7°C.

Lobelia cardinalis ‘Queen Victoria’

If your soil is not too cold or wet in winter, this wonderful tender perennial will survive outside in a sunny, sheltered spot (provided you can keep the slugs and snails off!). Cut back the top growth to 15cm and protect the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants in early spring when the worst of the frosts are over. Elsewhere, cut it back hard after lifting and store in crates of just moist compost placed somewhere cool, well-lit and frost free.

Lotus

Two-year-old plants flower much better because most blooms are produced on older wood, so these plants are really worth overwintering. For best results, keep them somewhere the temperature doesn’t fall below 7°C. Pot up plants individually without cutting them back and place on a windowsill in a cool room, or on the staging in a heated conservatory or greenhouse.

Melianthus major

In most gardens this half-hardy plant can be overwintered outside if you protect the roots with piles of dry leaves, manure, composted bark or straw. In very exposed gardens protect from cold winds too.

Osteospermum

African daisies can be difficult to overwinter as plants if your soil is heavy. On light soils you can get them through the winter by covering with open-ended cloches. However, on heavy soil you’ll be better off overwintering rooted cuttings. For best results, keep them somewhere the temperature doesn’t fall below 5°C – such as on a windowsill of a cool room, or on the staging in a heated conservatory or greenhouse.

Pelargonium (bedding geranium)

These expensive plants need to be kept somewhere the temperature doesn’t fall below 5°C. Pot them up individually and either place them on the windowsill of a cool room, or under the staging in a heated conservatory or greenhouse. If you have some larger plants, trim back this year’s growth by about one-third and keep plants ticking over during the winter by placing them in a greenhouse with a minimum temperature of 5°C.

Penstemon

Most penstemons can cope with light frosts, although the foliage will be cut back. If the soil is not too cold or wet during the winter, leave them in the ground where they have been growing. Cut back the top growth to 15cm and protect the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants in early spring when the worst of the frosts are over. Young plants flower better than older ones, so it is worth propagating in spring. Bring overwintered plants into growth during early spring by raising the temperature and giving a little water. You can also take cuttings now as insurance and keep them at a minimum temperature of 7°C.

Salvia

Salvias vary in their hardiness. Half-hardy perennial salvias can be left in the ground where they have been growing if the soil is not too cold or wet in winter. Cut back the top growth to 15cm and protect the roots and basal buds with a thick layer of manure or bark chippings. Uncover the plants in early spring when the worst of the frosts are over.

Scaevola

Young plants flower better than older ones, so it is worth propagating them now and overwintering them as rooted cuttings. Alternatively, overwinter one or two plants and take cuttings in spring. Get plants through the winter by keeping them somewhere the temperature doesn’t fall below 5°C. Pot up individually and place either on the windowsill of a cool room, or under the staging in a heated conservatory or greenhouse.

Verbena

Trailing verbenas are nearly all tender perennials so can be successfully overwintered as plants. Get plants through the winter by keeping them somewhere the temperature doesn’t fall below 5°C. Pot them up individually and place them either on the windowsill of a cool room, or under the staging in a heated conservatory or greenhouse. Young plants flower better than older ones, so it is worth propagating in spring. Bring overwintered plants into growth during early spring by raising the temperature and giving them a little water. Alternatively, propagate now and overwinter them as rooted cuttings.

Take cuttings as insurance

If you don’t have the space to overwinter all your plants, there is still time to take cuttings and root them in a heated propagator or on a sunny windowsill.

  • Choose healthy looking, non-flowering shoots and trim them to about 5-7cm, long just below a leaf joint.
  • Remove the lower leaves and any flowerbuds and insert them around the edge of a pot filled with cuttings compost.
  • Cover the pot with a clear polythene bag (not for bedding geraniums/pelargoniums) and place in a well-lit position out of direct sun.
  • Puncture the bag after rooting has taken place and keep the plants cool all winter.
  • Pot them up in spring and plant them out after the last frosts.
  • Don’t forget…

    Tender bulbs. Many summer-flowering bulbs, such as acidanthera, galtonia, gladioli, ixia and tigridia, can be overwintered successfully outside provided you live in a mild area and your soil is well drained. Cut back the plants at the end of the growing season and cover the ground with an insulating mulch of manure or composted bark. If your soil is heavy and wet, borderline-hardy bulbs, corms and tubers are best lifted, dried and stored somewhere frost free. Towards the end of this month lift the cut back plants and dry them on mesh elevated on bricks or place in boxes in an airy shed or greenhouse. Clean the bulbs/corms/tubers once the stems fall away easily, then dust with flowers of sulphur to help prevent rotting. Store in boxes placed somewhere frost-free and airy. Check monthly for signs of deterioration and discard any suspect bulbs/corms/tubers.

    Happy gardening!

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