June is often the first month of the year when the abundance of plant growth, conspiring with higher temperatures, results in the need for wholesale irrigation, rather than the selective watering of newly planted areas, pots, containers etc., which has been the priority up to now.
Thinking about watering has reminded me that the sales of metaldehyde based slug pellets will be banned, from around now, to allow time to use up old stock before their total ban, on outside applications, in 2020. The reason why this is linked to watering is because the way you water the garden has an effect on controlling the damage done by slugs and snails.
In dry weather slugs and snails are less able to move around, and therefore less able to nibble your precious plants, due to their mobility being based on slime production which relies on moisture being readily available. In hot, dry, spells they are more likely to stay below ground, or in cool hiding places, where they are safe from dehydration.
If you water your garden by spaying a fine spray of water, willy-nilly, over all the plants then you are creating the perfect conditions for these molluscally rascals to emerge and bite chunks out of your tastiest plants. The devastation is compounded if you water in the evening, so that the ground and foliage remains wet all night, just when slugs and snails are most active. Watering very early in the morning is a bit better but only if the water has time to evaporate from the foliage before the sun gets too hot. Wet leaves can become scorched if exposed to strong sunlight.
I don’t think I’ve mentioned it for a while, so this is the perfect opportunity, but incorporating seep hoses (a.k.a. ‘leaky hose’) into beds and borders may be the ideal way to irrigate in the most efficient manner. Seep hoses are easiest to install when creating a new planting scheme, from scratch, because the hose needs to be buried a few centimetres below the soil surface which is easiest before any planting takes place.
It is important to read the specifications, for whichever product you buy, because its porosity will determine the length you will require to ensure even watering over the whole area. If you need to install it in existing borders then it is possible, but more fiddly, as it will need to be buried, at the correct depth, while also weaving it around existing plants without damaging their roots. I pin it down with wire hoops, formed from stiff gardening wire, so that it stays in place even before it is covered over by the soil.
Most, if not all, black rubber seep hoses are made from recycled car tyres (check this is the case before purchase—I’ve only ever used the recycled variety) which is another bonus. Also, in addition to watering the plant roots and not the foliage, the fact that they are buried means that water loss by evaporation from the soil surface is minimised because the water is applied directly to the root zone, below ground, and not all over the plants and border.
They work at low water pressure, seeping over a long period of time, and are therefore well suited to being hooked up to a water computer. If programmed to supply water only during the hours of darkness then water loss by evaporation is reduced even further. When set up properly the soil surface should remain dry, except directly above the buried hose, which inhibits the activity of slugs and snails compared to a soil that is watered from above. Applying an organic mulch over the entire soil surface, including the buried seep hose, reduces water loss, by surface evaporation, even further.
Having had a relatively dry winter, following a hot and dry summer, there is a chance that watering restrictions may be necessary if this summer is also relatively arid. It goes without saying, even in the generally wetter south-west, that installing water butts and other water storage devices is pretty much de rigueur these days. Moving away from some of the most water-dependent plants, those that tend to wilt if not kept damp at the root, is another option. The trend towards ‘Prairie Planting’ consisting of more drought tolerant plant species, originating from grassland areas rather than ‘edge of woodland’ habitats, is a boon to creating planting schemes which are less dependant on good rainfall. They are also, by fortuitous happenstance, more mollusc resistant due to the fact that many ‘Prairie’ mainstays are less palatable to slugs and snails; ornamental grasses being a case in point.
I think of the large ornamental grasses as upright shrubs, in the mixed border situation, as they are similarly solid and act as a foliage foil to the more ephemeral flowering perennials. Miscanthus varieties have not yet reached their full height, they come into their own towards the end of summer, but the ‘Spanish Oat Grass’, Stipa gigantea, is in full bloom around now—although ‘bloom’ is a tricky term when applied to grasses which have more architectural flower spikes rather than ‘blousy’, petal based, inflorescences. I find that S. gigantea is less reliable than the bombproof, larger, Miscanthus sinensis and may be weakened, even killed outright, in severe winters. Having said that, its fountain of ethereal oat-heads, punching through a mixed planting, is so dramatic that it’s worth the risk
To inject extra colour into borders, especially now that the risk of frost is gone, it’s not too late to buy summer bedding and tender perennials as garden-ready plants. If you sowed your own ‘filler’ annuals, in early spring, then these are invaluable for plugging the odd gap, especially where spring bulbs have gone over. Alliums are the main bulbous plant making an impact now, taking over where tulips finished off, but they are notoriously unattractive as potted plants, their leaves tend to shrivel as the flowers come out, so are seldom sold as potted plants for instant effect.
Lilies are much more likely to be offered in garden centres and are a good ‘go to’ for plunging into border gaps. It’s always worth ordering some summer flowering bulbs, at the same time that you order your spring bulbs, to plant in pots and keep in reserve for this very reason. The choice of varieties is far greater, as bulbs, than that offered as ‘instant’ plants in garden centres. Growing your own is less expensive too.
Returning to the subject of watering, I’ll finish off with a reminder to add a feed to the watering can when watering plant displays in pots and containers. Plants which are expected to produce showy blooms, at least if regularly dead-headed, need to be fed artificially in order that they do not become exhausted before the summer is over. Follow the instructions on the packet for whichever fertiliser you prefer, I tend to use a balanced feed that is added to the can at a specified rate, as there is no point in overfeeding them.
At the end of the day, the most likely cause of container plants failing prematurely is a lack of water. Regular watering is vital because it’s very difficult to re-wet compost, once it has completely dried out, and the stress of becoming desiccated will weaken the plants. A weakened plant is more prone to succumbing to pests and diseases so diligent watering, with feeding every week or two, not only fulfils their maximum flowering potential but also saves you time and money in helping them survive with the least need for emergency intervention. Prevention is always better than cure!
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