May in the garden Russell Jordan
May is so full of life and rising sap that it’s easy to feel that almost anything is possible. Fundamentally it’s when the risk of frost is over and your tender plants can be gradually moved outdoors, ‘hardened off’, providing that you can whisk them back under cover if a seriously cold night is forecast. By mid May onwards it should be safe to plant out tender plants and border exotica like dahlias, cannas, salvias and their ilk.
If you are in the habit of propagating a lot of plants, and therefore have loads of perennials in pots, it’s a good idea to plant them into a ‘stock bed’ because it’s far easier to look after plants in the ground especially as, from this point on, watering becomes an inescapable chore. You’ll have enough on your plate with bedding displays, summer bulbs in containers and, most thirsty of all, hanging baskets, so the more that’s actually in the ground the better.
On the subject of watering I’d like to gently remind you that if a pot is allowed to dry out it cannot be rewetted by simply pouring water onto the soil surface. The only way to rewet totally dried out compost is to plunge the pot into a bucket of water, or tin bath in my case, until it is totally immersed. You’ll know when it is completely saturated again as no more air bubbles escape from the compost surface. I shouldn’t need to remind anyone how important it is to collect rainwater in water butts with the aid of ‘rain diverters’ fitted to gutter down-pipes.
When piped water was still just a ‘pipe dream’ (!) all houses of any size were equipped with water storage tanks, generally underground, fed by the gutters and rain run-off. A cast-iron hand pump, using the simplest form of non-return valve, provided the necessary low-tech means of extracting the stored water whenever required. It would seem sensible if we reinstated such rain storage solutions, wherever possible, especially now that submersible pumps make the extraction process effortless. Having said that, manual pumps are so much improved, by modern materials, that they still have their place where electricity is not easy to lay-on or where a back-up extraction method is required.
Watering is only going to be a real problem if we actually get a hot and dry summer. Pests and diseases, on the other hand, can become a problem whatever the weather. In wet years fungal diseases may be the greatest threat to plant health whereas in drier, warmer summers, pests, such as aphids, may multiply at such a rate that natural predation cannot keep on top of them. That’s why you must keep an eye open for early signs of trouble now, when swift intervention can nip the problem in the bud.
It’s not fashionable to use chemicals in gardening these days and many of the active ingredients, which were once available, have long since been banned. Preparations licensed for garden use may not be as effective as they once were but there is some justification in using them early in the season, rather than letting pests and diseases get the upper hand.
After I graduated from Agricultural College, where I did my degree in Horticulture, my first ‘sole gardener’ position included a regime of fortnightly rose spraying with alternating applications of pesticide (chiefly to kill aphids) and fungicide (to reduce the prevalence of black-spot). These days I reckon that if a rose can’t survive without constant chemical intervention then it probably shouldn’t be in your garden. Modern introductions have better disease resistance and are vigorous enough to withstand pest attack with minimal intervention. ‘Old Roses’, worth their salt, may get more black-spot and occasional aphid infestation but I choose to turn a blind eye to that if their blooms are the kind I cannot live without—blousy and generous with their scent.
Controlling slugs and snails is also important and if you do not agree with chemical means then now the warmer temperatures mean that biological controls, based on nematodes (microscopic worms), become effective. It would be very expensive to control a whole garden this way but to protect the most susceptible plants, especially those in pots, this method makes sense.
A similar biological control is available to control vine weevils and this is almost obligatory if you want to keep plants in pots over long periods of time. In garden soil vine weevils—actually it’s their voracious grubs that kill plants—seldom build up to damaging concentrations and go unnoticed. In the splendid isolation of pots, where they may not get predated, the grubs can completely consume plant root systems.
Herbaceous perennials will be rapidly extending up and out this month. To stop them flopping, when the inevitable winds and rains descend, insert a support system, such as pea-sticks, if you haven’t done so already. Ideally an upside-down ‘nest’ of interlocking twigs is woven over and around herbaceous perennials as soon as they emerge from the ground.
It’s often hard to envisage exactly how elaborate this ‘pea-sticking’ needs to be when the perennial is just an inch or two out of the ground. By now the degree of propping up required will be readily apparent and the beauty of pea-sticks is that their twigginess makes them ideal for pushing up against the flopping stems providing ‘instant’ support but also allowing for further expansion. Each clump may appear a little ‘trussed up’, for a day or two, but it soon settles down and the pea-sticks become all but invisible.
Fortunately May is so full of things bursting into life that even if you have no garden you will still be able to partake in the joys of colour and scent just by walking outdoors as woodlands and hedgerows are as good as any garden at this time of year. In fact, if you are not keen on primped and staked herbaceous borders, then modelling your own planting schemes on what you see in nature is no bad thing.