GardenHacker:
not your typical seedy site...

Companions work better in Tight Spaces

Square foot gardening works in apartments and on patios as well as in small outdoor gardens. The last thing you need is plants robbing each other of nutrients or making each other taste "off" (my parents have a camphor tree close to a grapefruit tree: the grapefruits near the camphor tree taste awful, while the other side of the tree tastes fine.). From square-foot-gardens.com: "...Reason number 2. Plants may help each other indirectly - mineral accumulators — plants use leaves they are going to shed as dumping grounds for unwanted minerals and by-products. That will then feed the micro-life and thus the future crops. There are minerals which are essential to the health of many plants. Some excellent examples for the square foot gardener are: iron which help leaf growth and is provided by beans as a companion; magnesium aiding leaf and root growth supplied by potatoes; manganese assisting in beet growth given by comfrey; ..." Link
Another great site ie kidsgardening.com, offering more reasons to companion plant: "...Gardeners often tuck garlic and onions between other vegetables for the same purpose. Here are some plants thought to repel specific pests:

• onions for carrot rust flies
• tansy for colorado potato beetles
• marigolds and basil for flea beetles on eggplant
• marigolds for Mexican bean beetles
• nasturtiums for squash bugs
• marigolds, mint, or thyme for cabbage moths..."

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