There are still those who prefer to have all their plants separate, each plant type confined to its own space. Vegetables should definitely not be allowed in the flower garden; herbs may be there only if more ornamental than useful, but don’t ever mix desert, country cottage or rose gardens together. That style of design is a matter of preference, and many gardens following those rules are very beautiful. They are usually also high maintenance, heavily fertilized, watered and sprayed, with poison set out for rodents.
The blending of useful and ornamental plants is certainly not a new idea, and yet it isn’t often done. When it is, gardeners should find that the loss rate of plants to pests is quite low, and the yield of the vegetables is high.
Why is this? For one thing, planting mixed seeds which include ornamentals, herbs and vegetables masks the scent of the most yummy plants from its preditors. There aren’t rows of the same type of plant for the insects to find. Since different plants take up different nutrients from the soil, the soil isn’t depleted of one particular nutrient, so mixed plantings usually make for healthier and tastier plants.
Wildflowers with cilantro, dill and basil not only are more successful and appealing to look at, but if let go to flower are excellent pollen sources for bees.
Allowing desirable plants to reseed not only saves you money, but makes the new plant hardy and adapted for your particular garden.
Of course mixing plants is what an edible forest garden is all about, although the mixing isn’t random. Each plant serves a purpose. I use fava beans as a great edible nitrogen-fixer, along with other beans, peas, sweet peas, lupine, and nitrogen-fixing trees and shrubs. Artichokes grow quite large, and their leaves when cut and left on the ground make superb compost, as do the leaves of comfrey. Artichoke leaves keep growing back, and the plant will produce many very yummy artichokes. (Artichoke hint: wipe Vaseline around the stem below the bud to keep ants and earwigs from finding their way between the leaves.)
Melons and squash make an incredible ground cover during the hottest months. Their large leaves shade the soil surface and block evaporation. Remember that raccoons aren’t supposed to like going through squash vines, so plant them around your corn.
Integrating your plants, especially when following the edible food forest guidelines, helps increase soil fertility (different plants remove different things from the soil). Mostly this is done by keeping the soil a more moist and inviting habitat for soil microbes and worms, but also by dropping their leaves which become mulch.