Now, looking into the science of soil may not have mass appeal, but I have been eager to learn more about this area of horticulture for some time. Not least because I have a fantasy of being in the ‘Gardeners’ Question Time’ audience, asking an incredibly pertinent, intelligent question about a plant problem (it is mandatory to describe the soil type), yet having the panel chortling at the wittiness of it – like I said, it is a fantasy.
This burning desire to understand the difference between a loamy sand and a sandy loam revealed itself in a semi-disastrous bread-making episode before Christmas. I’m not really familiar with the vocabulary of baking, but I am furnished with the words ‘crumb’ and ‘compaction’. The bread seemed to have the properties more likely associated with a combination of Bagshot sand and clay on which it had been raining for four days with a tractor parked on it(probably a Massey Ferguson MF 8480). The structure was disappointing, with few air spaces making it very dense. Fortunately it was the festive period, so after plying the family with a few sherries and disguising the sunflower loaded slices of wholemeal slates with layers of cheese and chutney, they dutifully ate it.
To my delight, my science tutor asked us to bring in a soil sample from home. After five minutes of the (im)mature students (me and at least four others) making various jokes/puns/innuendos about soil samples, we scribbled down a reminder to bring in the sample to be collected 24 hours before the day we were due to test the p.H.
I was working at the college nursery and horticulture unit the day before our science lesson. By the time I returned home it was dark and pouring down with rain, but I was not deterred. Ready with my empty ‘Chilli Jam’ jar, a trowel and a torch, I strode out into the darkness. I remembered the border areas where the urban foxes sometimes like to leave a little present and steered clear.
The next day in the laboratory, we set out our array of soil and set out on mixing it with chemicals in a test tube in the name of science. We set the tubes at an angle and waited for the solids to separate from the liquids to reveal the truth. Mine seemed to appear a fairly neutral green. It wasn’t really a surprise or a fair test – I hadn’t collected a number of samples from walking in a ’W’ shape across the garden, but I did get to mix chemicals and look like I knew what I was doing. There are no Rhododendrons where I live, Skimmias do badly and I keep my blueberry bushes in pots as acid this soil is not.
The best lesson I learnt that day was to go outside, dig up some earth and take it into your bare hands. Look at it carefully, rub it between your fore finger and thumb and listen to it. Roll it into a ball, then squish it. Does it fall apart or flatten out. Does it smear? What colour is it? We dug up soil from around the college site. Knowing that soil is made up of water, hummus, lime and clay, and considering our orientation, the use of the land and by looking at it and how it breaks up, we can find out a lot about soil and assess the porosity and permeability of it without the need for laboratory equipment.
I recently received an invitation from the Head Gardener at Nymans to check out some well flocculated loam. After looking up what this meant, I gratefully accepted (I was very chuffed when the flocculation process came up in our next science lesson). I have a few more soil lessons before my visit so I hope to come across as vaguely more knowledgable than I am now. In any event, it will be good practise for some fantasy future audience participation at ‘Gardeners Question Time’.