🍇 Blue Moon Wisteria

What it looks like

Why this variety

Blue Moon is the wisteria for gardeners who want the most bloom: a selection of the native Kentucky wisteria, with foot-long racemes of fragrant, lavender-blue, pea-like flowers that bloom in late spring and then repeat — dependably, up to three times in a growing season once established — on a vine hardy to minus 40 degrees, the hardiest wisteria of all. It was bred in Minnesota for cold hardiness, which means it blooms reliably even after winters that would kill an Asian wisteria’s flower buds, and it keeps blooming through summer, when most wisterias are done.

The trade-off is that Blue Moon is more vigorous than the American wisteria types — Kentucky wisteria grows faster and larger, reaching 15 to 25 feet quickly — so it needs a sturdy support and regular pruning, after each flush for repeat bloom and in late winter for shape. Give it a strong arbor or pergola, never a house wall, and prune to keep it in bounds. Note: like all wisterias, its seeds and pods are poisonous — do not eat them, and keep pods away from children and pets.

If you are new to choosing between cultivars, the Varieties Matter guide explains why the name after the plant matters as much as the plant itself. Blue Moon is a perfect example: it is not just a wisteria in the abstract, it is a wisteria with a specific job, a specific history, and specific strengths.

Florida honesty: Kentucky wisteria is a genuine statewide Florida plant in the sense that it thrives in Florida heat — its cold hardiness is a bonus, not a necessity, here — and Blue Moon’s triple bloom is a real asset in a long Florida season, giving fragrant flowers from late spring through summer. Give it sun, moisture, and a sturdy support, prune after each flush for repeat bloom, and enjoy a wisteria that out-blooms every other type in the garden.

How to grow

Plant in spring in full sun and moist, well-drained soil, against a sturdy, permanent support — a heavy arbor, pergola, or strong fence, never a house wall. Work worm castings into the planting hole, water through the first season, and prune after bloom to encourage repeat flowering, plus a late-winter shaping prune. American and Kentucky types bloom on new wood, so a hard late-winter prune costs no flowers.

Set plants 8-12 feet apart on a sturdy support in soil with a pH around 6.0-7.0. Work worm castings into the bed at planting and mulch to hold moisture. A well-fed wisteria plant rewards that care directly: steadier growth, better bloom, and a show that actually shows up.

Water & feeding

Keep soil consistently moist but never waterlogged — wisteria wants moist, well-drained soil, especially while establishing, and a vine that dries out stalls and blooms thinly. Water at the soil line, mulch to hold moisture, and feed lightly: castings at planting plus a balanced organic feed in spring is enough. Overfeeding makes leafy growth at the expense of flowers.

Common problems

• Vigorous escape — prune after bloom and in late winter, and never let wisteria climb onto a house, a roof, or a tree you care about.
• Failure to bloom on young vines — Asian wisterias can take years to bloom, but American and Kentucky types bloom young; be patient with any wisteria, and do not overfeed.
• Poisonous seeds and pods — wisteria seeds and pods are toxic; do not eat them, and keep pods away from children and pets.
• Damage to gutters and paint — twining stems crush gutters and lift paint; give wisteria a freestanding arbor, never a house wall.
• Leafy growth at the expense of flowers — overfeeding makes leaves, not blooms; feed lightly and prune for flowers.

Harvest

Cut racemes for bouquets in late spring, when flowers are fully open — wisteria lasts a few days in water and its cascading racemes suit tall vases, though the vine is best admired on its support. Prune after bloom for repeat flowering and in late winter for shape, and remove seed pods where children or pets could reach them — wisteria seeds are poisonous. The real harvest is fragrance: a wisteria arbor in bloom perfumes a whole garden.

Saving seeds

Blue Moon is a selected cultivar, so seed saved from it won’t come true — propagate it from cuttings or layering instead. The Saving seeds section of the Wisteria guide covers seed for the straight species.