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Vegetables

Here are the answers to some commonly asked gardening questions about vegetables and vegetable growing.

If you are unable to find the answer here, then why not send me an e-mail or visit the extensive grow your own veg section on RHS Online.

I would like to grow miniature vegetables, but do not know where to get the seeds from.Can you help please?

All the major seed companies sell seed of vegetable varieties that are suitable for growing as mini veg - and the packets are labelled as such; the varieties are grouped together as "Mini Veg Collections". Visit any good garden centre and you'll see them for sale or try any of the major companies that do mail order.

Also, most vegetables grow well in containers and by picking early - when they're young and have the best flavour - you'll also be able to achieve 'mini vegetables'.

Can you tell me what are the white marks on my marrow leaves?

Your marrow plants are suffering from the common disease powdery mildew, which proliferates in warm, dry conditions.

There are a number of different powdery mildews, but each one is specific to a particular plant or group of plants; this one only attacks cucurbits - which includes cucumbers, courgettes, squashes and melons.

The first symptoms are discrete white powdery patches which spread to cover the whole leaf, leading eventually to the leaf dying.

Badly affected leaves should be cut off and destroyed. Because the disease is worse in hot, dry conditions try to ensure the soil is kept constantly moist. Because the disease spores need a film of water to germinate in, make sure the leaves are kept dry - so always water the soil around the plant, rather than the plant itself.

The pods of my runner beans have developed black marks. Can you tell me what's wrong and whether the beans are edible?

Your beans are suffering from the disease bean anthracnose, which affects both runner and dwarf French beans.

Brown stripes develop on the stems, reddening on the underside of the leaf veins. This is often followed by the leaves withering and dying. Rounded, reddish spots then develop on the pods and soon spread to the developing beans.

Affected plants should be destroyed and healthy ones could be sprayed with a suitable fungicide to protect against infection. Next year make sure you grow your beans in a different part of the garden and spray to protect them if necessary.

I grow onions from sets. Some years I get a very good crop but sometimes it is a total failure like this year. The sets seem to start growing as they should and then come to a stop and make no progress at all and I harvest the same sized onions that I planted! It happens about every third year. As I sometimes get a good crop I don't know what I am doing wrong.

If you can provide any suggestions I should be most grateful.

The main problem with onions not performing is through poor soil preparation, planting too early (which checks growth), the soil being too dry and plants not being adequately watered through dry spells and diseases such as onion mildew. Also planting poor quality sets doesn't help - buy from respectable firms like Unwins and Marshalls. Having said that, poor weather last year affected the quality of this year's sets which didn't help.

This year has been terrible for onions - I've seen failed crops all over the country.

I'm sure by checking on the above growing conditions and making alterations, you'll improve your onions next year.

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Garden answers

Vegetables

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