Peter Dowdall: Why these plants are catnip to every gardener

Alliums are bulbs we plant in autumn and come spring, they make us realise we've done rather well. They combine beautifully with catmint, nepeta, and geraniums

Cats love playing with catmint, nepeta. Planted at the foot of your alliums, it will fill 'the understorey' with a soft haze of grey-green, hiding everything beneath while the great spherical heads float above it as though suspended in mid-air. File pictures 

There are plants that stop you in your tracks in other people's gardens, and alliums are exactly that kind of plant. The spherical heads held high on tall straight stems, bobbing gently in a May breeze, have a quality that is just captivating. Architectural, stylish, colourful and easy to grow, May is when they come into their own, and if you have never grown them, let me tell you, you should.

They are bulbs you plant in autumn, and come spring, the foliage arrives first, broad, strap-like and fresh and luxuriant with all the promise that a new spring brings. This is when you think you have done rather well. Then, as the energy of the plant begins to redirect itself upward and into flower production, those same leaves start to yellow and wither at the edges.