(Question)
why won’t my wisteria bloom? it is about 7 years old
(Answer)
Lack of blooms is a common problem with wisteria. It can be difficult to bring to flower and ofter may take about 7 years to reach a flowering stage. Young plants grown from seedlings can take 20 years to flower, so hopefully you purchased your wisteria from a reputable garden centre and it was grown from cuttings or by grafting and is a named cultivar.
- Wisteria flower best in full sun – excess shade is detrimental
- Take care to water in dry spells between July and September, when flower buds are forming for next year, as drought at this time can result in failure to bloom
- Be aware that sharp spring frosts can damage developing flowers, causing them to drop before they open, or to develop in a distorted fashion
- Heavy fertilizing, especially an excess of nitrogen, results in heavy stem and leaf growth which discourages flower bud formation
- On poor soils, potassium may be lacking so try applying sulphate of potash in spring to promote flower bud formation
- Prune wisteria twice a year, in July or August, then again in early spring to encourage flower formation
Toronto Master Gardeners have produced a Gardening Guide for getting Wisteria to bloom. Please click on the link below.
Hopefully this will help and your wisteria will indeed bloom soon. Do not give up yet!