During this last arid month, I have seen the near-demise in gardens of the excellent spurge, Euphorbia griffithii, 'Fireglow', which is a great plant in itself and also a good foil for jewel-coloured tulips in late spring. It spreads happily in sun or shade, but curls up and seems to start dying from the top down when too dry.

The normally ineradicable, weed-like Solidago, also known as Goldenrod and now coming into flower, has been drooping miserably during this spell of drought.

So too has the free-running and very pretty Lysimachia clethroides, a late-summer flowerer with arching flowering stems, made up of dense clusters of tiny white flowers, that show up very well in partial shade near the edge of light woodland.

The tall, sweetly-scented and old-fashioned border phloxes are another case of an otherwise easygoing herbaceous perennial, which cannot withstand bone-dry feet for any length of time. They droop dreadfully when stressed by lack of water, though this can usually be remedied by playing the hose on them for at least half an hour, if you catch them in time. The imposing North American, Joe Pye Weed, (Eupatorium purpureum), is another case in point.

The problem with these and many other essential perennials is that they all need good, free-draining but reasonably moist soil to thrive.

Here in Ireland, many of us take those conditions for granted, so we don't bother to mulch around plants to conserve moisture, because we have good reason for believing there's always more rain on the way.

Only this time there hasn't been any rain for a long time, and as a result lots of good plants are literally dying on their feet for the want of a good soaking.

I cannot emphasise enough that you must really soak them until the ground around is saturated and not readily absorbing any more water on the spot.

That's the only way to get a supply to their roots. To understand the meaning of a proper watering for plants in the open ground, consider the correct way to water pots and just copy.

That is, if the water goes through the compost in a pot, then it's too dry and you must either soak by immersion, or water from the top until it stops running freely through the holes in the bottom.

The other great . . . and less wasteful water trick is to mulch generously, but this is only effective if the ground is damp or wet. Otherwise, it just blows away or stops the next bit of rain getting through.

After a good round of watering, you can use anything to hand to keep the moisture in around plants, including grass clippings, which means you won't be adding them to the compost heap immediately.

This is a good thing, as too many grass clippings packed in together make a compost heap airless and slimy and stops it doing its job of breaking plant matter down into useable garden compost.

Stones or pebbles also make good mulch and water is likely to hang around longer if there are little holes, pockets and hollows in which it can linger.

On the other side of the spectrum are herbaceous perennials that stand up well to dry conditions. They are the unnamed and unshowy but neat and upright white Shasta daisy and the amazingly good white Japanese anemone, 'Honorine Jobert', for which we should all be eternally grateful.