PLANT OF THE WEEK

50C perfectly possible on a fine summer’s day. And overnight winter temperatures are often 2C lower in a tunnel than outdoors.

I increase ventilation by having “stable doors” at the front, with the upper door open throughout the summer and the lower one closed to exclude questing poultry beaks. I raise or lower a fixed sliding door at the back of the tunnel to help control temperature and use it to nip out with a weed bucket to the tunnel’s compost bin.

I’ve tried every conceivable watering system over the years: drip irrigation from a header tank; under soil leaky hose; and the trusty watering can. The drip system is self-regulating and the leaky hose is fine when you’re around but it could also be controlled with a timer. But I’ve come to favour a hand hose because I can monitor how plants are growing and how much water they’re needing (although it’s also very relaxing to sip a pint of home brew while pretending to be doing something useful).

This hand watering also lets me notice the progress of unwelcome weeds, for they enjoy the benefits of tunnel life as well. A mulch keeps them at bay.

I cover layers of newspaper with grass clippings and top them up until the plants close canopy, taking care the grass doesn’t touch and scorch stems.

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On a mild winter’s day the tiny white flowers fill the garden with sweet scent. An evergreen shrub with box-like leaves. It needs a shady site protected from the harshest frosts.