Permaculture Central Coast was recently asked for some ideas on what to plant under fruit trees that wouldn’t compete with the trees for nutrients.
Meg McGowan from Permacoach provides some great options.
The notion of plants competing with each other has largely been debunked. Soil life is dependent upon air, moisture, and organic matter, including living roots. The forest is our best pattern for how much life can be mutually beneficial in the same space. There are a few trees, like macadamias, that are allelopathic and they are easy to identify because nothing much will grow under them, but most fruit trees will be happier with any kind of ground cover. Consider plants in these categories:
Fragrant: Plants with strong scent help to confuse creatures that would otherwise be attracted to your delicious fruit. Many popular herbs fall into this category including all of the thyme varieties, oregano and rosemary.
Soil miners: Typically have long, deep tap roots that mine minerals from deep in the soil and store them in their leaves while also opening up the soil and improving drainage. They are used for chop-and-drop mulching. Both comfrey and vetiver grass are permaculture classics. Borage and daikon radishes left to go to seed double as pollinator attractors and also have edible flowers.
Soil doctors: These plants provide a range of benefits to your soil. All of the mustards are natural fumigants that help to prevent pathogenic fungi, and marigolds will help to deter unwanted nematodes.
Legumes: These plants form symbiotic relationships with soil bacteria to fix nitrogen. Most (like peas and beans) will just use that nitrogen to support their own growth but if you chop and drop a legume or choose one that has been bred to improve the soil it will shed root mass and release nitrogen. “clever clover” is a great example.
Pollinator attractors: As well as providing beautiful flowers, these plants can improve your yield by increasing the rate of pollination. Stack functions by choosing edible flowers. Yarrow, borage, daikon, carrots, and mustard all work this way.
Living mulches: These plants form a thick, weed suppressing layer under fruit trees that suppresses weeds, shades the soil and helps to modify the temperature due to transpiration. Both Commelina (scurvy weed) and mother of herbs fall into this category, and stack functions by being edible.
Photo by Skylar Zilka on Unsplash