As the growing season has suddenly come upon us, I’ve been doing a bit of reading up and reflecting on some gardening conundrums.
John Harrison, in his wonderful Essential Allotment Guide writes about soil thus:
‘Your soil is made up of rocks and rock dust mixed with organic matter that we call humus [which] holds everything together and at the same time stops the rock dust from setting into a solid, cement-like mass‘.
This makes so much sense, as I despair at my garden soil which looks like rocks (bits of chalk and flint) and rock dust set into cement. Not enough hummus … The station garden has been blessed with hummus rich soil as we’ve built it up from scratch in raised beds. Very little of our underlying chalk rocks and rock dust have gone into it.
Top or bottom watering?
Why, I was wondering, are our seedlings showing slight signs of nutritional deficiency? The tiny seedlings were planted up in early May in 7cm pots in a mix of peat-free multipurpose compost and vermiculite. When we’ve been planting them out now, I’ve noticed how the roots only show as a tangle at the bottom of the pot. They have been getting pot bound.
Eureka moment: we’ve done so much watering from the bottom, i.e. having the pots sit in water, so the roots have gone straight to the bottom. This may be a good thing, as once the plant is planted out, the roots should run deep. But it does seem to have meant that they ‘exhaust’ the 8cm pot more quickly than if watering had been done consistently from the top. Now I’m not entirely sure this is a plausible hypothesis; will probably need to check with a real horticulturalist … perhaps via the RHS advisory service we so far haven’t used?
Many of us at the garden love coriander, but all of us have failed to grow viable quantities in the past. I know that coriander likes rich soil, and that to avoid it going to seed, it is useful to place it in partial shade.
Here’s a good summary from a US site, which confirms coriander that is not easy to grow:
“Cilantro [Coriander] is tricky because several factors can cause it to bolt. Avoid transplanting for this reason, and avoid hot conditions as well as too much moisture. It does best in light, well-drained soil in partial shade, in relatively dry conditions. Once it blooms, the seeds ripen suddenly, in only a couple of days, so care should be taken to prevent self sowing or simply losing those useful seeds.”
What I hadn’t realised is that, of course, it has a long tap root, so it needs to be grown in deep soil. I’ve always tried growing it in a pot so I suspect the pots weren’t deep enough.
So I’m out now to plant out our coriander seedlings in a ceramic glazed pot 35cm deep (is this enough?) with a mixture of general purpose peat-free compost and our recycled organic matter mulch (should be rich enough). I’ll place the pot by the wall so it gets some shade. And assuming it grows well, we then have to be careful to remove any flowers.
We’ll see what happens …