Tuesday, 7 April 2009

Exciting Organic Control with Companion Planting!

By Marc from GardenDesk

Exciting news in my vegetable garden - the Horseradish survived the winter and is looking great!

Why is this exciting? Not just because I like horseradish sauce to spice things up from time to time. No, I will stay excited about this horseradish even if I never harvest it. I didn't harvest any last year as a matter of fact.

The main job for this wonderful plant is not to be eaten, although we do harvest some. This horseradish bed is strategically located in the very center of our garden. It's main purpose is to ward off these guys:

This is the Blister Beetle, what used to be my garden's arch enemy! Before planting the horseradish, the Blister Beetles used to decimate my heirloom tomatoes each year. They could make a real mess in a big hurry.

As I've mentioned many times before, I do not believe in using any kind of chemical insecticide. A few years ago (before I knew about using horseradish) I had no way to stop these beetles.

Blister Beetles get their name from the fact that they contain a toxin called cantharidin that will make your skin break out in blisters if you come in contact with it. Usually you would need to touch a crushed beetle to break out, but some people can have an allergic reaction just from touching one of the beetles. The blister beetles in my garden ate a lot of tomato foliage, but the most disgusting part about them was that they left huge droppings behind as well!

Enough already! They disgust me so!

I bet you are grossed out by now as well. Sorry. I only show the negative in order to focus on the positive. I was determined to beat this bugs organically. I searched and searched for something I could combat them with and found my answer in an unlikely place.

The famous book, Carrots Love Tomatoes, by Louise Riotte is the foremost authority on companion planting ideas. In the past I had used her ideas about planting certain plants alongside other crops in which each kind of vegetable or herb has a beneficial effect on the other. I had read the book many times before when mapping out where to plant each vegetable in the garden. I always focused on what crop grows better in the presence of what other crop, but I never really noticed that she addressed natural controls for pests too! She listed horseradish as a plant to keep blister beetles away.

I tried it and it worked really well. In the first year with horseradish, the infestation was cut by about 75% and last year I had only a few beetles. The horseradish is looking even better this year, so maybe I will have no beetles!

She also writes that using horseradish root in water as a spray will deter many insects. She discusses deterrents for animal pests as well, like growing morning glories to keep deer away and cucumbers to keep raccoons away. Radishes next to those cucumbers will keep the striped cucumber beetle at bay - that worked well for me last year!

All of these pieces of organic advice is why Carrots Love Tomatoes is on my list of 25 favorite gardening books. The book is not the main thing here though. The exciting part is that there are many natural ways to deter pests and there are many natural ways to aid crops by planting other beneficial crops in close proximity. These are the things that I enjoy learning as my neighbors drench their food crops in chemical pesticides and herbicides.

I encourage all gardeners to stay vigilant in finding natural means to grow bountiful harvests. Organic gardening is so much better! Don't you agree?

Keep Growing!

- Marc