As we recommend with all plants, it is key to regularly water newly planted plants in the months after planting. With wisteria, you'll need to set up supports prior to planting.
With pergolas be sure to use quality timber, either treated softwood or hardwood, and ensure the posts and crosspieces are thick enough to support a mature vine. Where you are not growing wisteria, cement the posts for extra support. You'll need to run galvanised wire up the length of the posts to support the stems as they grow. (Simply tie them in.) Use eye hooks to provide space for circulation and growth. Once the vine has grown over the top, and is stable, the wire can be removed. You can encourage branching at the top by pruning off the tips.
With walls, run galvanised wire horizontally across the wall at multiple heights, tying in vines where appropriate, just like you would for an espalier. Eye hooks provide space for circulation and growth. A tree stake can be used to provide extra support and may necessary if you are growing up a fence.
Ensure you plant 0.6m (2ft) from the wall/pergola leg as to leave enough space to support a mature vine. Dig a hole, twice the circumference of the pot. Ensure the pot sits roughly level with the soil, with the graft point above the soil. Infill, the remaining space with a mix of compost and garden soil, but do not compress the soil.
In terms of care, watering is important especially during the summer months. They will need a thorough watering twice weekly during dry spells.
For the best blooms, you'll need to prune your wisteria, to ensure it concentrates energy in flowering rather than vegetative growth. You'll also need to reduce vegetative growth to ensure it doesn't become too unruly. To do this, prune after flowering, cutting back this year's growth to 6 inches. Prune the same growth again in late winter, reducing them to three to five buds. Make sure, you don't prune off this year's growth entirely, as wisteria flowers on the previous year's growth.
Wisteria plants are easy to grow. Below we address some common queries:
- Position: Wisteria plants require full sun. Only sinensis varieties are suitable for light shade. As a rule, wisteria species with long racemes look best growing up pergolas, while species with short racemes look best growing up walls. We recommend you buy floribunda varieties for pergolas and sinensis, brachybotrys and frutescens varieties for walls for this reason. Lastly, as wisterias form thick woody roots, we recommend you plant only once, and do not move from place to place.
- Soil Types: Wisteria is part of the legume family and is therefore able to fix nitrogen from the atmosphere, and therefore does not need fertilising as much as other plants. Wisteria will thrive in any soil, providing it is not compacted or waterlogged.
- Hardiness: Wisteria originate from North America, China and Japan, which have colder winters than the UK, and are henceforth fully hardy.