Each time the rains dry up in spring just as the plants push out their sappy shoots I puzzle over what must be happening underground. Is it the big fat powerful-looking roots that elbow weaklings aside and suck up the dwindling moisture in the soil, or is it the fine thread-like roots in their masses that win the greater share? I suspect the threads, with their much greater surface area, do better in separating what water there is from its adherence to soil particles.
How they can keep supplying multiplying leaves with the liquid they need is beyond my imagination. The suction in each stem is transmitted to each minute rootlet – which has its own needs to keep it growing, too. The forces at work to keep every shoot and leaf turgid and functioning are awesome.
There has not been a millimetre of rain here since the scattering we had in March: the five weeks of the year with the greatest demand for water have been supplied entirely from moisture held in the soil by surface tension – and yet I hardly see a limp or drooping shoot.
Certainly growth has been slowed down. I started watering perennials a week ago. Aruncus sylvester (already with flower buds) quickly shot up to three times the height. Delphiniums looked as if they are about to flower at knee height; watering has made things a little better. A young Magnolia ‘Star Wars’, which always seems to overdo its flowering, had scarcely a leaf two weeks ago but fifteen flowers. A can of water a day and it presents a much more balanced picture of flower and leaf. Does localized watering with cans create bedlam below as every rootlet smells water and heads into the damp zone?