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By Martyn Cox
As I write this, I’ve just returned from a dog walk. For my sprocker spaniel, the highlight was being let off her lead at Canoe Lake, but for me it was strolling along local streets. Apart from admiring some wonderful front gardens, I discovered many ornamental plants that had clearly jumped garden walls to establish in the surrounding landscape.
Among those to catch my eye were an English lavender growing in a gap between kerb stones, several hollyhocks brightening up a back alley and a hebe clinging to the face of a wall. Down one street, I was excited to find several seedling tree echiums (a native of the Canary Islands) thriving in cracks in the pavement.
I admire these plants whose seeds establish in gaps and less hospitable places and appreciate all they do to soften our urban environment – they help blur the straight lines of pavements and walls, disguise drains and add beauty to places that are sometimes on the austere side.
Left: Martyn’s sprocker spaniel, Lisla / Right: A self-seeded hollyhock
My fascination with ornamental plants that go rogue started in childhood. I grew up in the East Midlands, where Victorian factory walls were studded with butterfly bushes (Buddleia davidii), sometimes flourishing within crumbling mortar, 20-30m above the ground. This shrub is also a common sight across our city, whether colonising brickwork or more natural places, like Milton Common.
Given that it’s so widespread you might think this bee and butterfly magnet was a British native, however it was introduced from China in 1896. First grown at the Royal Botanic Gardens, Kew, it was later discovered to be a prolific self-seeder, and the first garden escapee was recorded in 1922.
Another plant that’s widely naturalised is Erigeron karvinskianus. Native to Mexico, this spreading, daisy-like plant made its debut here in 1780 and is found in walls and paving cracks across the south. I planted several in my front garden a few years ago and it’s now a firm fixture of the street scene.
Apart from enjoying ornamental plants in the urban environment, I welcome those that self-seed in my garden. As far as I’m concerned, any bare spot is a planting possibility for an opportunistic species and if nothing seizes the opportunity, then I’ll take the initiative and plant it up myself.
Creeping thyme is brilliant in cracks in paving, providing a durable mat of aromatic leaves and bee-friendly flowers in summer. If you have gaps in walls, try cuttings of sempervivum, delosperma or alpine sedum. Improve the chances of plants rooting by prising out loose mortar and filling the void with John Innes No.1 compost.
Martyn Cox is an award-winning garden writer, author and presenter, who runs his own garden maintenance, mentoring and consultancy business in Southsea. He can be found on Instagram @gardenwithmartyn
Posted in: Home & Garden
