It’s a fact. The bindweed has gone bananas. I took my eyes off a client’s back garden for one fortnightly session in order to trim the front hedge and weed the paved drive, and before I knew it, the magnificent mature mahonia tree was completely smothered in it, not to mention the surrounding roses and spiraea bushes.
There are two types of bindweed; Calystegia sepium - commonly known as hedge bindweed or bellbind, and Convolvulus arvensis - also known as field bindweed. Both plants have a similar, white rhizomous root system. These rhizomes are brittle, and the plant is capable of regenerating from just a small section of broken-off rhizome, making cultural control of this persistent perennial weed particularly difficult.
The roots can penetrate up to five metres deep, and spread out to as much as two metres in just one growing season. This year’s combination of sunshine and showers appears to have created the optimal conditions for maximising its spread.
Calystegia sepium - Hedge bindweed
Calystegia sepium is what I most commonly come across in urban gardens in south Manchester. It has heart-shaped leaves and white trumpet-like flowers. If you look away for about three seconds, you find that it has entwined and smothered most of the garden.
Calystegia sepium - Hedge bindweed
Convolvulus arvensis - Field bindweed
Convolvulus arvensis has pink trumpet-shaped flowers which are smaller than those of the Calystegia sepium, and tends to be more problematic in long grass, or is found scrambling over bare soil.
Convolvulus arvensis - Field bindweed
In both cases, dig down and try and remove as much of the white rhizomes as possible, without breaking them. Autumn digging can also be a good opportunity to have a go at doing this. I have been doggedly adopting this approach in my own garden for the last two years, and the problem is definitely much reduced.