What to do in the garden this week: Plant half-hardy annuals

Gardeners are tough, but, just occasionally, the odds are stacked against us. Last winter felt like an eternity; spring has been tardy and fickle, making us vigilant of weather forecasts and vulnerable plants. In mid May, we had unexpected frosts here at Bryan’s Ground, and a succession of miserably low day and night temperatures after a few pleasant weeks; seed sowing became a game of Russian roulette. Things that had leapt ahead in that mild spell slunk back, seeming exhausted by it all.

William Cowper’s words of more than 200 years ago rang in my ears: ‘Who loves a garden loves a greenhouse too’, at times translating itself in my head to ‘who loves a garden needs a greenhouse’.

The days are long gone since our Edwardian structure, measuring some 40ft by 15ft, was heated by hot water pumped from a monster boiler through yards of 6in-wide cast-iron arteries. Early in the year, we built an Andalusian-inspired pool within it.

At 3ft high (but with a water depth approaching 5ft, due to an extra measure of excavation), the tops of its foot-wide surrounding walls are a stage now for summer’s show of bright exotica in many kinds of containers. Hours spent dibbling nasturtium seeds into small fibre pots, and mixing barrowloads of nutritious compost for lilies, cannas and small-flowered begonias, have paid off.

Ginger lilies (hedychium) rise triumphant and large-leafed caladiums spread their elephant-ear foliage in shady corners. Regal and angel pelagoniums bask in terracotta pots on the staging and trailing ivy-leafed kinds mimic a lava-flow of blackberry purple (in the variety Barbe Bleu) that will go on being reflected in the pool’s deep water for many months to come.

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I’m growing several kinds of nasturtiums from packets bought at Silene Nurseries (www.silene.be) on a visit to Belgium two years ago. Their smell-hardly a scent!-along with those of elder and lemon balm is a pungent reminder of my gardening childhood. I did wonder if the knobbly little seeds were still viable, but those of Black Velvet and Burning Embers were good; only Cobra was less successful, having perhaps been stored inappropriately since they were purchased.

The back (working) end of the greenhouse, partitioned from the much larger display area, is my plant factory and production area for tomatoes (Roma, Harbinger, Gardener’s Delight, Tumbling Tom and Fox Cherry this season) and various kinds of basil sown in old enamel washing-up bowls. Pots of mint, flourishing in sombre gloom beneath the slatted staging, were encouraged into early growth in time for modest pickings at Easter.

In March, I planted summer-flowering bulbs in individual pots to fill gaps in the garden, this year raising dozens of Black Star and Green Star gladioli to stand among euphorbias and salvias in a south-facing border. Small pots stuffed with scented white-flowered Gladiolus calli-anthus (aka acidanthera) came in handy for tubs placed outside in sheltered sunny positions.

Ventilation is a key factor in maintaining a healthy greenhouse, and we’re lucky that ours has large roof and side windows that open and close by means of a simple yet delightfully effective manual mechanism.

The presence of strawberries growing in traditional strawberry pots encourages the sporadic intrusion of blackbirds, wrens and robins in search of juicy morsels, but these I tolerate:
in exchange for a peck at a tasty fruit or two, they’re also quick to gobble up any potentially destructive aphids and thus help to secure a balance between nature and my own entirely fabricated attempts to manipulate ideal conditions for a range of plants with extraordinarily diverse needs.

The pleasures of a greenhouse are many, and although we’ve placed a couple of chairs inside ours, we have so far resisted a lounger. That, I fear, could only lead to an excess of unproductive languid moments.

Bryan’s Ground, Stapleton, Herefordshire LD8 2LP (www.bryansground.co.uk) is open on Saturday, Sunday and Monday afternoons until July 12

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