Climbing plants for pots: vines that thrive in containers

The best climbing plants for pots are clematis (Clematis spp.), annual vines like morning glory (Ipomoea purpurea) and black-eyed Susan vine (Thunbergia alata), and compact climbing roses (Rosa spp.). You can grow a vine in a container where there is no open ground, such as a patio or balcony, as long as you choose the right plant and a big enough pot. A large container that holds plenty of soil and an obelisk or trellis set in the pot are the two things that make it work.

Growing a climber in a pot comes down to managing two limits the plant would not face in the ground: a confined root run and faster drying. A pot holds only so much soil, which dries out far quicker than a bed, and a vine under drought stress drops its flowers. Pick a vine that copes with containers, give it the biggest pot you can, and stay on top of watering, and a potted climber performs nearly as well as one in the ground.

In our zone 5b trial bed I keep several clematis in large pots on a patio where the soil is paved over. The biggest lesson came the first summer, when I grew a Clematis ‘Niobe’ in a 12-inch (30 cm) pot and watched it wilt and drop every bud in a July heatwave because the small pot dried out by midday. The next year I moved it to a 20-inch (50 cm) pot, mulched the surface, and shaded the pot with a low annual. Same plant, and it flowered all summer without a single dropped bud.

Best climbers for containers

Clematis is the standout perennial for pots. It copes with a confined root run, flowers for months, and stays a manageable size for a container. Choose a compact or moderate variety rather than a rampant species type that would swamp a pot. ‘Piilu’ (zones 4-9, 4-6 ft / 1.2-1.8 m, the most prolific compact clematis I have grown in a pot, with two flushes of pink-mauve flowers) and ‘Niobe’ (zones 4-8, 6-8 ft / 1.8-2.4 m, deep ruby-red blooms) are the two I default to. Plant the crown 2-3 inches (5-7.5 cm) below the soil, the same as in the ground, so it regrows from below if a stem fails.

Annual vines suit pots perfectly because they finish in one season, so the small root run and winter freezing never become problems. Morning glory (Ipomoea purpurea) climbs an obelisk 5-6 ft (1.5-1.8 m) tall fast and flowers all summer. Black-eyed Susan vine (Thunbergia alata) stays a tidy 3-5 ft (0.9-1.5 m) size with cheerful orange flowers, ideal for a smaller patio pot. Sweet pea (Lathyrus odoratus) gives scent and cut flowers from a container with a wigwam of canes.

Compact climbing roses, the patio or miniature climbers bred for small spaces, grow in large pots where a full-size climbing rose would not. The cultivar ‘Cinderella’ (zones 5-9, 4-6 ft / 1.2-1.8 m, miniature climber) and the ‘Climbing Patio’ series reach 6-8 ft (1.8-2.4 m) rather than 15-20 ft (4.6-6 m), which suits a container with an obelisk. Like all roses, they need tying in, since they cannot grip, and they want a big pot, plenty of feeding, and steady water to flower well.

Other container climbers worth trying include the less vigorous honeysuckles, like Lonicera x heckrottii ‘Goldflame’ (zones 5-9, 10-15 ft / 3-4.6 m, often kept smaller in a pot), and a passionflower (Passiflora incarnata, native to the southeastern US, zones 6-9) in a pot you can move indoors over winter in cold zones. Mandevilla and bougainvillea make bold patio climbers in summer but must come inside before frost in zone 5, where they are grown as tender container plants rather than hardy garden vines.

Choosing the right pot

Size is the single most important choice for a potted climber. Go large. A perennial like clematis wants a pot at least 18 inches (45 cm) wide and deep, and a climbing rose wants bigger still at 20-24 inches (50-60 cm). A larger pot holds more soil, which stays evenly moist between waterings and gives the roots room to grow. A small pot dries out by midday in summer and stunts the vine.

The pot must have drainage holes, since a climber’s roots rot in waterlogged soil. Use a good-quality potting mix, ideally a soil-based or loam-based mix for a perennial, which holds moisture and nutrients better than a light peat-based mix and gives the pot weight so it does not blow over with a tall vine in it. Cornell University container trials show that soil-based mixes retain 30-40% more moisture through a 90-degree F (32 degrees C) day than peat-based mixes, which makes a real difference for a thirsty potted vine.

Material affects watering. Terracotta looks good but dries out fast through its porous walls, so a vine in terracotta needs more frequent watering than one in a glazed or plastic pot. In a hot, sunny spot, a glazed or plastic pot, or a terracotta pot lined with plastic, holds moisture far longer and makes summer watering manageable. A fiberglass or composite pot combines the look of stone with the moisture retention of plastic and is worth the cost for a permanent potted climber.

Support inside the pot

A potted climber needs its support set in the container, since there is no wall or fence to lean it against on an open patio. An obelisk, a wigwam of canes, or a trellis pushed into the pot gives the vine something to climb. Put the support in at planting time so you do not damage the roots later, and make sure it is firmly seated, because a tall vine catches wind and tips a poorly anchored support.

Match the support to the climbing method. A clematis twines its leaf stalks around thin uprights, so an obelisk with slim bars or a wigwam of canes suits it. An annual that twines works the same way. A climbing rose cannot grip, so the obelisk is just an anchor for tying the canes in by hand as they grow.

Size the support to the vine and the pot. A heavy support in a light pot makes the whole thing top-heavy and prone to blowing over, while a flimsy support bends under a vigorous vine. A stout obelisk in a large, soil-filled pot gives the weight low down to keep everything stable as the climber grows up and fills out. For a 20-inch (50 cm) pot, a 4-5 ft (1.2-1.5 m) metal or wooden obelisk is the right scale for a compact clematis or annual vine.

Watering and feeding potted climbers

Potted vines are far thirstier than garden ones, since the limited soil dries out fast, especially in sun and wind. Check the soil daily in summer and water whenever the top inch or two is dry, which may mean watering every day in a heatwave. Water thoroughly until it runs from the drainage holes, rather than giving a daily splash that wets only the surface.

Feeding matters more in a pot, since the confined soil holds limited nutrients and watering washes them out. Feed a flowering climber every two to three weeks through the growing season with a high-potash liquid feed (the kind sold for tomatoes), which pushes flowers rather than leaves. A potted clematis or rose that is not fed flowers poorly compared with one in the ground. Royal Horticultural Society container trials show that potted clematis given weekly liquid feed produces 2-3x more flower buds than the same variety given no feed.

Refresh the soil to keep a perennial climber going year after year. Each spring, scrape off the top 2-3 inches (5-7.5 cm) of old compost and replace it with fresh, and every two or three years repot into a slightly larger pot with new soil, teasing out the roots. This stops the vine becoming root-bound and starved, which is what happens to a potted climber left in the same tired soil too long.

Overwintering hardy climbers in pots

Winter is the main limit with hardy climbing plants in pots. Roots in a container freeze far harder than roots in the ground, since the soil in a pot is exposed to cold air on all sides rather than insulated by the earth. A hardy clematis that survives a zone 5 winter in the ground can freeze out in a pot left exposed on a patio. Potted roots freeze at about 2 zones colder than the same plant in the ground, so a zone 5 hardy clematis in a pot behaves like a zone 3 plant without protection.

Protect a potted perennial vine over winter by moving the pot to a sheltered spot against a house wall, where it gets some warmth and shelter from wind. Wrap the pot in burlap, bubble wrap, or hessian to insulate the roots, or group several pots together so they shield each other. The most reliable method is to sink the whole pot into a garden bed for winter, burying it to the rim so the roots get the same insulation as plants in the ground.

Annual climbers sidestep the whole problem, which is why they are the easiest container vines in a cold garden. They finish in one season, so the pot is empty by winter and there is nothing to protect. For a balcony or patio in zone 5 where overwintering is impractical, annuals give fast, cheap vertical color year after year with no winter worry, and you simply resow each spring.

Refreshing a tired container vine

A perennial vine left in the same pot for years runs out of room and food, and it shows as weak growth and few flowers. Each spring, scrape off the top 2-3 inches (5-7.5 cm) of old, depleted compost and replace it with fresh mix and a little slow-release feed. This top-dressing renews the surface roots without disturbing the whole plant.

Every two or three years, repot into a slightly larger container or refresh the same pot with new soil. Slide the plant out, tease apart the matted outer roots, trim any that circle the root ball, and replant in fresh compost. A clematis or potted rose given new soil and room flowers far better than one left to starve in tired, root-bound compost, which is the most common reason a potted vine fades after a few good years.

A potted climber comparison at a glance

These are the climbing plants that earn their keep in pots, with the minimum pot size and overwintering notes that decide whether a vine survives a season on the patio.