Learning about companion plants - Nasturtiums

Continuing the theme of plants I've never grown, I present you with nasturtiums.  At least I've seen nasturtiums before.  They're pretty plants with rather rounded leaves and yellow, orange, and red flowers.  I decided to grow them after reading that they attract predatory insects. After what happened to my bean plants last year, I'll take any organic help I can get!

As a Companion Plant
It is a companion to radishes, cabbage family plants (cabbage, collards, cauliflower, kale, kohlrabi, broccoli and mustards), cucumbers, and can improve their growth and flavor.  It is said to deter whiteflies, squash bugs, striped pumpkin beetles, cucumber beetles and other pests of the cucurbit family.  It is a good trap crop for aphids (particularly the black fly aphid), especially the yellow-flowering varieties.  Studies say it is among the best at attracting predatory insects.  Problem insects include leafminers and flea beetles.

There is conflicting information on whether it is okay to plant nasturtiums nearby/with tomatoes.  Some sources say that nasturtiums can develop bacterial wilt as a result of being nearby to tomatoes, peppers, and eggplant.  Others say that they're great together because the nasturtiums will deter a variety of insects which can plague tomatoes (and other plants).

Growing Nasturtiums
It likes poor soil with low moisture and no fertilizer.  Better soil yields more foliage and fewer flowers.  Nasturtiums may be potted among garden beds in order to isolate them into poor soils to encourage more flower growth.  Seeds may be direct sown after the last frost.  Can attract hummingbirds. 

Consumption of Nasturtiums
Edible flowers and leaves; commonly used in salads.  Has a peppery flavor similar to dandelions and borage.   Nasturtium seeds can be a substitute for capers.  Pick seeds while green, put in a container with vinegar and soak for 3 days.

I have had a hard time trying to find useful nutritional information on the nasturtium. A few pages pointed to watercress, however, information found on wikipedia state that that's a mistake.

Despite the Latin name, watercress is not closely related to the flowers popularly known as nasturtiums (Tropaeolum majus).

As a result, the best I can do is to state that a number of websites all say that Nasturtiums have a considerable amount of Vitamin C and Iron.