Climbing flowering plants for a trellis: best picks for zone 5

The best climbing flowering plants for a trellis are clematis (Clematis spp.), climbing roses (Rosa spp.), honeysuckle (Lonicera sempervirens), and sweet pea (Lathyrus odoratus), with morning glory (Ipomoea purpurea) for fast annual color. A trellis gives a vine a flat, open frame with narrow gaps, which suits twining stems and grabbing tendrils best. Clematis is my first choice, since it wraps its leaf stalks around thin slats and covers a panel within a season or two without any help from you.

The thing most plant tags skip is how each climber actually holds on. Get that wrong and you spend the summer tying a plant to a frame it was never going to grip. A trellis works for vines that twine, like clematis and honeysuckle, and for tendril climbers, like sweet pea. It does not work on its own for a climbing rose, which has no twining stems or tendrils and needs tying in by hand.

In our zone 5b trial bed, I ran a side-by-side test along a 6-ft (1.8 m) cedar trellis. On the left I planted Clematis ‘Jackmanii’ (zones 4-8, 10-12 ft / 3-3.7 m). On the right I planted a climbing rose ‘New Dawn’ (zones 5-9, 12-20 ft / 3.7-6 m). By August the clematis had climbed the full panel under its own steam and covered it in deep purple flowers. The rose had thrown out long canes that flopped sideways until I tied each one in. Same trellis, two different jobs. The clematis ran itself. The rose needed a hand every week.

How flowering climbers attach

Trellises favor three of the four main climbing strategies, and understanding which method your chosen vine uses saves hours of frustration. Twining stems, the largest group, wrap the entire stem around a support: clematis (leaf-stalk twiner, not stem twiner), honeysuckle, and morning glory all climb this way and need a thin member no thicker than a pencil to wrap around. Tendril climbers send out thin coiling threads that grab wires, string, or netting: sweet pea, nasturtium, and the cup-and-saucer vine (Cobaea scandens) are all tendril climbers. Scrambling roses have stiff, arching canes with neither twining stems nor tendrils and must be tied to the support by hand. The fourth group, clingers, are not well suited to a slatted trellis because they need a flat continuous surface; climbing hydrangea and Boston ivy do better on a wall or solid fence than on a trellis with gaps.

Best flowering climbers for a trellis

Clematis sits at the top of the list for good reason. It twines its leaf stalks, called petioles, around any support thinner than a pencil, which is exactly what a slatted trellis offers. The large-flowered hybrids, like ‘Jackmanii’ (deep purple, 4-inch / 10 cm blooms) and ‘Nelly Moser’ (pale pink with a carmine bar, 6-8 inches / 15-20 cm), put on the showiest display. Plant the crown 2-3 inches (5-7.5 cm) below the soil surface, deeper than most perennials, so the plant can regrow from below ground if a stem snaps or wilts from clematis wilt (a stem-rot fungal disease that can kill a vine in days). Missouri Botanical Garden Plant Finder recommends burying two nodes below the soil line, not just one, to give the plant a deep reserve for regrowth.

Climbing roses give you the classic cottage-garden look, but they need work. A climbing rose throws out long, stiff canes that have no way to hold on. You tie them to the trellis with soft ties, and here is the trick most people miss: bend the canes sideways rather than straight up. A cane trained horizontally flowers all along its length. A cane left to grow vertically blooms only at the tip. Royal Horticultural Society trials at Wisley confirm that horizontally trained climbing roses produce 3-4 times more flowering shoots per cane than vertically trained ones on the same plant.

Honeysuckle is the climber to pick when scent matters most. The native trumpet honeysuckle, Lonicera sempervirens (zones 4-9, 10-20 ft / 3-6 m), twines up a trellis and feeds hummingbirds all summer without the invasive habit of some Asian types. Its fragrance peaks in the evening. The cultivar ‘John Clayton’ (zones 4-8, 6-10 ft / 1.8-3 m, clear yellow tubular flowers) is a Longwood Gardens introduction prized for clean foliage and repeat bloom from May through July. I prune it right after the main flush of bloom to stop the base going woody and bare, which is what happens when honeysuckle climbs unchecked for a few years.

Sweet pea (Lathyrus odoratus) is the annual I plant every spring for cut flowers and scent. It climbs by tendrils, thin coiling threads that grab netting or string strung across the trellis. The vines reach 6-8 ft (1.8-2.4 m) in a season and produce flowers from late spring into early summer before heat shuts them down. Sow the seeds direct in early spring while the soil is still cool (45-55 degrees F / 7-13 degrees C), since sweet pea germinates better in cold ground than in summer heat. Pick the flowers often, because the more you cut, the more the plant produces. Cut-flower trials at Cornell have recorded 25-30% more bloom on plants harvested daily compared to plants left to set seed.

How to match the climber to your trellis

The gap between the slats decides which plants will climb on their own. Twining vines and tendril climbers need something thin to wrap around. A trellis built from 1-inch (25 mm) wide slats works for clematis and honeysuckle. If your trellis has wide slats or thick posts, stretch garden netting or run wires across it so the stems have something narrow to grip.

A climbing rose changes the setup entirely. Since it cannot grip at all, the trellis is just an anchor point for tying. Build it from sturdy timber (2x2 / 38x38 mm minimum) and fix it firmly to the wall or set it deep in the ground (18-24 inches / 45-60 cm post depth for a 6-ft / 1.8 m panel), because a mature climbing rose carries real weight and catches wind. A flimsy trellis that holds a clematis fine will lean and pull loose under a heavy rose.

Install the trellis 2-3 inches (5-7.5 cm) off the wall, not flat against it. Stems need room to wrap around the back of the slats, and the gap lets air move behind the foliage. Tight against a wall, the leaves stay damp and powdery mildew sets in fast, which is a common problem on clematis and climbing roses in a humid summer.

Flowering climbers for fast color

Annual vines fill a trellis in a single season, which makes them the cheapest way to test a spot before you commit to a perennial. Morning glory (Ipomoea purpurea) germinates fast and climbs 8-10 ft (2.4-3 m) by late summer, opening trumpet flowers in blue, purple, or pink each morning. Soak the seeds overnight before sowing to speed up germination, since the seed coat is hard.

Black-eyed Susan vine (Thunbergia alata, zones 9-11 grown as annual) is another quick annual that suits a smaller trellis on a patio. It throws out cheerful orange flowers with dark centers from midsummer until frost, with individual blooms 1-1.5 inches (2.5-3.8 cm) across. It climbs by twining, so it grabs a slatted panel without help. In zone 5 it dies with the first hard frost, so treat it as a one-season plant or move it indoors as a houseplant.

Hyacinth bean (Lablab purpureus) grows fast and tall, with purple stems, lavender flowers, and glossy purple seed pods 3-4 inches (7.5-10 cm) long that last into fall. It twines vigorously and covers a tall trellis by August. The pods and seeds are toxic raw, so keep it away from edible gardens if children pick at the garden.

Perennial climbers that return each year

For a trellis you plant once and keep for years, clematis and climbing hydrangea are the most reliable in cold-winter gardens. Clematis dies back in winter and regrows from the crown each spring, which is why planting it deep matters. A clematis crown set 2 inches (5 cm) under the soil survives a hard zone 5 winter far better than one planted at the surface. Royal Horticultural Society data show that deep-planted clematis recover from clematis wilt roughly 80% of the time, compared with about 30% for shallow-planted ones.

Climbing hydrangea (Hydrangea anomala petiolaris, zones 4-8, native to Japan, Korea, and Sakhalin) is slow to start but worth the wait. It clings by aerial roots, so on a true trellis it needs the first few stems tied in until the roots take hold of the frame. Once established, it climbs on its own and covers a panel with white lacecap flowers in early summer. It tolerates more shade than most flowering climbers, which makes it useful for a north-facing trellis where roses and clematis sulk.

Trumpet vine (Campsis radicans, native to the southeastern US, zones 4-9) flowers hard in full sun and feeds hummingbirds, but it grips by aerial roots and grows aggressively, reaching 25-40 ft (7.6-12 m). Give it a stout trellis fixed to a sturdy structure, not a light decorative panel, because it can pull a flimsy frame apart over a few years. Prune it hard each spring to keep it in bounds.

Planting and training for a full trellis

Plant your climber 6-12 inches (15-30 cm) out from the base of the trellis, not tight against it, so the roots sit in open soil rather than the dry strip right at the wall. Lean the young stems toward the frame and tie them loosely until they catch. For twining vines, this first guidance is the only training they need.

Water deeply through the first season while the roots establish. A flowering climber under stress drops its buds before they open, which is the most common reason a new clematis or rose disappoints in year one. Mulch the base to keep the roots cool and the soil evenly moist, since clematis in particular likes its head in the sun and its feet in the shade.

Prune to the right rule for each plant. Spring-flowering clematis (group 1, like Clematis montana) blooms on old wood, so prune it after flowering. Group 2 large-flowered hybrids bloom on old and new wood and get a light tidy in late winter. Group 3 summer types like ‘Jackmanii’ bloom on new wood, so cut them back hard to 12 inches (30 cm) in early spring. Get the timing wrong and you cut off the flower buds for the year, which is why so many gardeners report a clematis that grows well but never blooms.

Combining climbers on one trellis

A single climber gives one season of flowers, but two on the same trellis stretch the color for months. The reliable pairing is a clematis through a climbing rose: the rose gives the structure and early bloom, and a late clematis weaves up through it and flowers when the rose pauses. Plant them 1-2 ft (30-60 cm) apart so the roots are not fighting, and let the clematis use the rose as living support.

Space the plants to suit their vigor. A rampant clematis like Clematis montana (zones 6-9, 20-40 ft / 6-12 m) will smother a delicate companion, so pair vines of similar strength, or give the stronger one its own end of the trellis. For a long trellis, plant several climbers spaced out rather than expecting one to cover the whole run, which leaves gaps and bare patches where a single vine cannot reach. Staggered bloom times keep the trellis in flower from late spring through fall.

A trellis comparison at a glance

These are the flowering climbers I rate most highly for a zone 5 trellis, with how each one climbs and how well it takes to a slatted panel.