We’ve been wondering about the behaviour of our tomatoes and our courgettes, both of which are now doing well in the sun, but have particular, intriguing characteristics which have puzzled us. I’ve checked up on the varieties we’re growing to see if we can solve the puzzles.

Tomatoes

We have four tomatoes: two ‘Maskotka’ and a ‘Vilma’ in a grow bag, and a ‘Vilma’ in a 30cm pot. The Maskotka seeds we got free at the time of Big Dig Day, and the ‘Vilma’ I bought back in the dark days of February, and I have forgotten why.

All four plants are bushy, happy and producing lots of tomatoes, but most significantly not growing upwards. Do we need to do the usual pinching out of side shoots and staking? Looks unlikely: it turns out we’re growing special container varieties.

‘Vilma’

The Thompson & Morgan site gives this description: “Specially bred for growing in containers, Tomato ‘Vilma’ is a compact bush variety reaching 60cm (24″) tall. This compact plant produces a heavy crop of sweet and juicy, cherry tomatoes each weighing 20g (0.7oz) over a long picking period. Tomato ‘Vilma’ is easy to grow in the greenhouse or outdoors and will not require side shooting or training. Height and spread: 60cm (24”).”

‘Maskotka’

“A dwarf bush variety that has been specially bred for growing in baskets and containers, with cascading stems that fall gently over the sides of their pots. Tomato ‘Maskotka’ produces a heavy crop of bite sized cherry tomatoes weighing 25-35g (1-1¼oz) each, with a delicious sweet flavour. The fruits of this compact variety have good resistance to cracking whether they are grown under glass or outdoors.”

Courgettes: ‘Gold Rush’ = gold leaves?

We’re growing two types of courgette: ‘Gold Rush’ and ‘Black Forest’. Both have quite idiosyncratic characteristics. Both seem to be growing well now and both are producing courgette-lets. ‘Gold Rush’ has yellow fruits … and all our plants, both in the station garden and in my garden, have some bright yellow leaves. Funnily enough, they look healthy. There’s new growth and no sign of wilting or browning. It’s curious that in my garden, the ‘Gold Rush’ are growing alongside green courgettes, which don’t seem to have the yellow leaf problem.

Hmm … is this a mineral deficiency (magnesium? potassium?) or is it a characteristic of the plant? A quick flick through various web forums suggests that many other gardeners have this same ‘problem’. In both cases, the beds were manured in the autumn, so mineral deficiency seems a little unlikely. It may be a problem of take-up: something is stopping the plants taking up the nutrients in the soil.

The solution seems to be: 1) try tomato feed to increase potassium (we’ve started, but this could in fact be the problem) and 2) try a foliar feed of Epsom salts. This is used to promote more balanced take-up of magnesium, which can be compromised when plants are given potassium-rich feeds.