IT HAS been positively sub-tropical here, with temperatures in the mid twenties and humidity at 60 per cent and above.

The heat, coupled with several heavy downpours, has been great for plant growth, but it’s not so easy for the gardener.

Gardening in hot weather can be an exhausting business; it’s important to take regular breaks, drink lots of non-alcoholic fluids, to work in the shade if possible and to do heavy jobs like mowing early in the morning or late in the day.

Wear a hat if you’re prone to heat stroke, and plenty of sun screen even if you’re not fair-skinned - time can be deceptive in the garden, it’s easy to stay out too long and get sunburnt.

Plants in pots and hanging baskets will need watering daily, but don’t waste energy watering in the heat of the day. Soak each pot in the evening, so the water has time to percolate down through the full depth of the pot during the night. Some well-watered plants may still flag during the day, especially if it’s breezy. This is called physiological wilting, occurring when the plant leaves transpire water faster than the roots can take it up. There’s not much you can do when this happens to a plant in the border, but plants in pots could be moved to a shadier spot or the pot stood in a bowl of water.

Pests seem to enjoy hot weather. I went out this morning to photograph a whorled Solomon’s seal (Polygonatum verticillatum), which had been looking particularly splendid just a couple of evenings ago – it’s like a taller, thinner and altogether more elegant version of the common Solomon’s seal. Imagine my surprise when I found it peppered with small, grey caterpillars busily chomping away at the foliage! These turn out to be sawfly larvae, a common pest of Solomon’s seal, with cousins who specialise in eating gooseberry and rose leaves. I spent a happy half hour picking them all off, but my photograph will have to wait until next year now, the plant is too disfigured to look its best.

Some plants that are looking at their best, revelling in the hot, damp weather, are the ferns. We grow several species in shadier parts of our garden, and they’ve all done well this year apart from the South American Blechnum chilensis, which suffered from last year’s cold winter. My favourites are the Dryopteris or buckler ferns, D. erythrosora with its coppery red foliage and D. wallichiana, whose mid-ribs are deep brown, almost black against the dark green fronds.

I also have a soft spot for one of our native ferns, the hard fern, Blechnum spicant, which is currently looking just lovely coupled with the silver-white leaves of Brunnera macrophylla ‘Jack Frost’.

Jobs for this week: Stake and support dahlias, gladioli, chrysanthemums and other top-heavy border plants.

Pick herbs for winter use before they come into flower. Tie them in small bunches and hang them to dry in a cool, airy room.

Summer prune wisterias to encourage next year’s flowers, shortening each of the long growths back to six or seven leaves each. Cut back leading growths by one third, tying them to a framework of trellis or stout wires.

Mulch runner beans with a thick layer of compost, up to two feet wide on either side of the rows. This will cut down on weeds, feed the plants and keep the rows cool and moist.