Blooming Times: A Guide to Watering

This month, Flo Whitaker explains how to keep your garden irrigated throughout summer - and makes an appeal for ‘slow watering’

If questioned about plant nutrients, I always say, “Feed the soil – not the plant”. When it comes to watering advice, the theme is much the same. Well- conditioned soil readily holds onto moisture and supports plants in times of drought. The key is plenty of humus; well-rotted, organic material that’s moisture-retentive and provides a rich habitat for soil microbes, worms and much else besides. If possible, make your own compost and leaf mould mulches – and never chuck away old potting soil. It may have become tired and dusty, but, when sprinkled onto the soil surface, will continue to play a useful role.

Sacks of mulch are available from garden centres and various companies offer large bulk bags delivered to your home, which can be very cost-effective, particularly if you share a load with a neighbour. 

Bone dry potting compost is virtually impossible to re-wet, as anyone who’s returned from holiday and found gasping pot plants will attest to. A drench of water merely guarantees wet feet, as water gushes through the pot within seconds. Why does this happen? It’s a two-fold problem: Firstly, the humus material has become shrivelled and its surface area greatly decreased, thus eliminating any moisture-grabbing abilities. Secondly, water molecules have surface tension. This phenomenon can be easily observed after rain in the form of water droplets on leaves. 

Gently tap a leaf and watch the droplets roll around like balls of mercury. That’s surface tension – and is why water molecules struggle to attach themselves to desiccated soil; they simply roll straight through it. A few drops of washing- up liquid, (a mild detergent) added to a can or bucket of water will break the surface tension and aid re-wetting. 

A small drought-stricken pot plant can be plunged entirely into a bucket of detergent-water, (use a brick to weight it down), left to soak for an hour, then drained. When tackling a larger pot, water gently from above, placing a drip tray underneath so it can absorb run- off water from the base. For big patio pots, you may have to excavate plants and start from scratch, soaking the root balls before re-potting. This is a total faff, but unless roots are thoroughly re- hydrated, plants will not recover. 

Hosepipe bans used to be exceptional events, but have become a regular occurrence in our region. We must adapt to climate change and learn to employ water strategically. Hosepipes are, of course, highly convenient, but can be wasteful and damaging if used in random fashion. A fierce jet of water can shred leaves, blast compost out of pots and deliver too much – plants can suffer from overwatering as well as drought.

Select a gentle spray setting and always water at soil level where plants can efficiently use it. Watering in early morning is ideal as it gives plants the opportunity to take up moisture reserves before the sun gets to work.

Evening watering is also beneficial, although nocturnal slugs and snails,attracted by damp conditions, may prove troublesome. Using watering cans is undoubtedly protracted and labour intensive, but there are advantages to ‘slow watering’. When lugging heavy cans about, the mind is more attuned to efficient watering practises and the gentler pace gives time to notice finer details; the seedlings that require thinning, the plant that needs tying in, the birdbath that could do with a scrub – all the little things that are easily overlooked when you’re charging around with a hose. 

You can never have too many watering cans - even the smallest garden needs several. Keep them filled and strategically placed, so there’s always one to hand. Place a stick or cane in each can; if a creature falls into the water, it can climb out again. 

Water butts come in many types; from traditional barrels to slim, wall- mounted tanks, cleverly designed for limited spaces. If you have just one useable downpipe, connector kits can be purchased at minimal cost, allowing several water butts to be joined together. Most plants prefer the ‘softer’ nature of rainwater; particularly ericaceous plants and potted shrubs/trees. 

Various auto-irrigation systems are available, including traditional osmosis set-up’s, along with electrical and solar-powered versions. They can have a significant outlay, but may provide an invaluable solution, particularly if physical health is an issue, or regular extended travel is anticipated.

In times of water scarcity, prioritise fruit and vegetable plants as yields fall significantly on dry soil. Potted plants in direct sun will probably require daily watering. Regularly check newly-seldom make extensive roots, so put them high on your watering checklist. Recycled ‘grey’ water from showers and baths and the rinsing water from hand- laundering and washing-up water, (not dishwasher waste), can be safely used on established border plants and shrubs. Avoid using grey water on seedlings and vegetables, particularly leafy/salad crops, as they have a low tolerance for soap residues. 

As for lawns; forget them. Yes, they may turn brown and crispy, but that precious water can be better employed elsewhere. Grass is one of the most robust plants on the planet. Your lawn will start greening-up within days of a downpour - then you’ll have to start mowing. Again ...