Companion Planting

Up to this year, I've always kept my three balconies separate as far as use was concerned. At home the front balcony (the one I look out on and sit on) was for plants in flower, while the back was the herb garden (just outside the kitchen door) and the nursery where I had the seedlings and the cuttings, plus the perennials not currently flowering - chrysanthemums in the spring and summer for instance. Then, my office balcony had a few flowers right in front of the window, but tucked away around the corner (well out of sight of my clients - now why?) was my vegetable garden, with its beans and courgettes and tomatoes.

This year though, I've changed. Nine times out of ten in the past, the veg and the herbs didn't make it - they were decimated by whitefly and red spider mite before they came anywhere near harvest. So this year I've changed tack - I'm companion planting.

The idea behind companion planting is simple. Growing certain plants near others improves the chances of the second group doing well. Why? Several reasons ...

Firstly, some plants will protect others from pests, diseases and environmental factors. So if you pop those in amongst others which are susceptible to those problems, they'll have some degree of protection. So here for example, I've got marigolds next to my tomatoes. Marigolds give off a smell which whitefly can't abide. So in avoiding the marigolds, they'll also have to stay away from the tomatoes. At the same time, I've got peppers planted by the tomatoes. The strong sun hasn't hit here yet this year, but when it does, the tomatoes will shelter them and provide humidity. There's some garlic in there too, as there is around my roses, to repel aphids.

Then there are plants which are supposed to benefit the growth and flavour of others - like basil for tomatoes. That's in there too but it's not quite big enough to see in the photo. A pity that you can't grow mozzarella - I'd have a complete caprese in one container :)

Some plants will attract beneficial insects. For example, marigolds (yes, they crop up all the time) attract hoverflies , and hoverfly larvae like to munch away on aphids.

And finally, there are the sacrificial plants. This one's sad. You put in something that you know is irresistible to a particular pest, in the hope that it will leave the other plants, which you want to save, alone. There are a couple of nasturtiums tucked in with the roses too to attract aphids.

Why bother? Because every pest that can be deterred with another plant is one that doesn't have to be squirted with some foul, polluting chemical.

It's not all good news of course. Some of the worst pests don't seem to respond to companion planting at all - and, as every summer, my big fear is red spider mite. I've yet to find a plant that will repel it, and all those marigolds are actually going to attract it. And there's always the fear that if you attract them to sacrificial plants, they'll spread. Oh, my poor tomatoes.

And then there are the incompatibles. Just as some plants seem to like being together,and thrive, others seem to hate each other and do badly. Keep your onions away from your peas and beans for example and your tomatoes away from your potatoes. Not always easy if you're gardening in a small space like a balcony.

So what do you grow with what and what should you avoid planting together? You'll find loads of lists on the web - try these Google searches for instance Companion plants and Companion planting. Or if you have a specific plant in mind, just add it to the search box.

But whatever you search for, if you do find a plant that will repel the dreaded RSM, please, please let me know ...