Just good friends...

By Carole Davies - 12/03/2009

It’s strange isn’t it?  Just like people, certain plants get along with some plants more than others. Not only do they ‘get along’ - they simply thrive.

 

This is the basis of companion planting, a system that has been handed down from gardener to gardener - from times when cottage gardeners lacked space to grow their fruit, vegetables and flowers in separate beds.

 

By trial and error, gardeners found that some species did better when they were planted in close proximity to certain other plants and began to plan their planting around such ideas.

 

You have no doubt heard of growing garlic in close proximity to roses, because it deters aphids; the same is also said of lavender. Garlic is reputed to help the growth and flavour of beetroot, and the leaves of the beets in turn contain a relatively high proportion of magnesium - which makes their leaves a welcome addition to the compost bin.

 

Marigolds, known for their effectiveness in deterring aphids, are quite often grown close to tomatoes, potatoes and roses - in particular, the variety Tagetes minuta (Mexican marigold) releases secretions into the soil some three or four months after sowing, via its roots. The secretions are believed to inhibit the growth of some plants, including such beauties as bindweed, couch grass, celandine and ground elder. In my book, growing marigolds is valuable just to get rid of the bindweed. Be warned though, that marigolds will do as much harm to the bean family, and to brassicas, as they are beneficial for potatoes, tomatoes and roses.  

 

Alliums - the onion family - are extremely valuable as companion plants. And no doubt anyone that grows carrots knows to interplant with a member of the onion family, be it salad onions, chives, garlic or leeks because the stronger smell of the onion confuses the carrot root fly and it, quite literally, loses its way. Onions also deter slugs so planting some of those more tender leaved salad crops amongst the onions will help to protect them. Alliums can also help protect plants from fungal infections, so planting strawberries in close proximity to them can help prevent the strawberries developing mould.

 

I seem to have gone on about this quite a bit, but it is familiar territory as I chose this subject as a specialist assignment on organic gardening when I was doing my HNC in Horticulture some years ago. Because of this I have read many books on the subject that delve into the science behind the theories in much more detail than I have room to mention here.

 

There are great long lists of beneficial companions to be had, whether from books or from the world wide web. If you do have access to a computer just try googling ‘companion planting’ or ‘beneficial planting companions’ and you won’t be disappointed at the amount of information that you’ll unearth.

 

There are also numerous books on the subject; one I can recommend as very easy reading is Bob Flowerdew’s ‘Complete Book of Companion Planting’ (£14.99 from the MatureTimes bookshop 01872 562324).  

 

Quite apart from the health benefits of companion planting to your crops, with a bit of forethought the planting up of these ‘companions’ can make very attractive and interesting borders - providing tasty crops and beautiful views at the same time.