Companion planting combines diverse plants in an informed manner to bring a balanced ecosystem into the garden. This approach to gardening has been used by organic gardeners for decades. The idea is to plant herbs and flowers with vegetables to create sustainable gardens with better crop yields.
The “three sisters,” corn, beans, and squash, are perhaps the best-known example of ideal plant companions. They support one another's growth, maximize the growing area's crop yield, and provide a solid diet for their cultivators.
Another well-known group of companions is that of legumes (like beans), with clover and alfalfa. Bacteria invade the root hairs of legumes and make nodules where these beneficial Rhizobium nitrogen-fixing bacteria live. The nitrogen these bacteria fix becomes available to the legume plant and the soil around its roots. Legumes can be worked into the soil, renewing and replacing nitrogen. This reduces the amount of manure and chemical fertilizers needed for heavy-feeding plants.
Companions can help prevent pest problems by repelling pests or attracting the beneficial insects needed to keep down the population of insect pests. Onions are one plant that repels some pests. Marigolds contain thiophene, which deters root nematodes. Chives planted alongside roses repel aphids. Nasturtiums act as a decoy crop for kale and tomatoes by attracting aphids away from the more desirable edibles (once the nasturtium plant has attracted aphids, it is removed from the garden before the aphid young develop wings). Aromatic herbs like basil, rosemary, lavender, and sage, will repel many pests. Mix these in with pest-susceptible plants. The presence of diverse plant species disrupts the ability of herbivorous insects to discover host plants for feeding or egg-laying. The time wasted on non-host plants reduces the reproductive efficiency of specialist insects.
Lists of specific companion plant combinations can be found on websites and in gardening books. Find the best friends for your garden plants, to create sustainable gardens with better yields. Remember to experiment, observe and record how these companions work in your own garden.
PLANT SALE! Mark your calendar for our plant sale on Saturday, May 18, 2024 from 9 am–noon. The sale will be held at the Master Gardeners Demonstration Garden at Patrick Ranch. The plants, which are selected to thrive in our climate, have been propagated by UC Master Gardeners of Butte County. For more information and a partial list of the plants that will available, visit our website.
Are caterpillars chewing on your cabbage? Aphids browsing your Brussels sprouts? Cucumber beetles snacking on your squash? Keeping insect pests from attacking your garden veggies can be a problem, but help is on the way: Just invite your neighborhood beneficials to the banquet in your garden.
You don't need to order beneficials from a garden catalog; most are already present in your garden. Your job is to give them the food, water, and shelter they need to thrive, and they will reward you by patrolling your garden.
- Avoid the use of pesticides. Pesticides tend to be indiscriminate, killing beneficial insects as well as insect pests. If chemical control is necessary, use the least disruptive materials, such as soaps, oils, microbials, or botanicals.
- Create a garden that celebrates diversity. Include both annual and perennial ground covers, shrubs, trees, turfgrass, and some permanent arrangements, such as stone paths and decorative rock accents, which will provide shelter for insect predators. Clumps of native grasses make good overwintering sites for a variety of predatory insects.
- Plant lots of different kinds of flowers. Flowers provide pollen and nectar that beneficials need and that will sustain them when pest populations are low. Flat-topped flowers, such as dill, parsley, cilantro, and Queen Anne's lace, are especially attractive to tiny parasitic wasps – some of the most effective beneficial insects in the garden.
- Provide water. A shallow dish of water filled with pebbles or gravel and placed in a sheltered area will give small beneficials a safe place to slurp. Change the water regularly and avoid a puddle to prevent mosquitos which may harbor West Nile Virus from laying their eggs there and multiplying.
- Plan for a full season of bloom. Keep beneficials in your garden year-round by including varieties of flowering plants that bloom throughout the year.
- Go native. Allow some corners of your yard to grow naturally. Native beneficial insects love native vegetation.
- Tolerate a small number of pests. This will provide a continuous food supply for beneficials. Try “sacrificing” some plants in the garden, or if resorting to pesticides, make spot-treatment applications, leaving reservoirs of pests on which beneficials can survive.
- Eliminate ants. Ants interfere with the ability of predators to control aphids and scales. Applying a sticky material such as Tanglefoot to the base of affected plants will keep ants away.
UC Master Gardeners of Butte County are part of the University of California Cooperative Extension (UCCE) system. To learn more about us and our upcoming events, and for help with gardening in our area, visit our website. If you have a gardening question or problem, email the Hotline at mgbutte@ucanr.edu (preferred) or call (530) 538-7201.
By Michelle Ramsey, Butte County Master Gardener, August 23, 2013
The scary-looking, ominously-named wolf spider is actually a beneficial insect. Wolf spiders belong to the class Arachnida andare members of the family Lycosidae (derived from the Greek word lycos, meaning wolf). Wolf spiders stalk their prey like wolves do; they do not spin webs or use silk to subdue prey. They are fast-moving, aggressive ground predators with excellent eye sight (helped in no small part by the fact that they have eight eyes, arranged in three rows: the first row has 3 small eyes, the second has 2 large eyes and the third row, closest to the top of the head, has 2 medium-sized eyes). They are nocturnal and hunt for insects mainly at night. They are likely to be found on the ground in open areas like farm fields and grassy environments, or harboring in ground tunnels, amidst pieces of firewood or debris. There are more than 2000 wolf spider species, with body sizes ranging from less than one millimeter to 30 millimeters (.04 to 1.2 inches).
Wolf spiders provide natural control of harmful insects. The Carolina Wolf Spider (Hogna carolinensis) is the largest of the wolf spiders. It is brown with black markings. Its body can measure more than one-inch long (and the whole spider can measure 4 inches across, from legs to legs). Female wolf spiders are larger than males; their undersides are solid black. Because some wolf spiders are large and hairy, they are sometimes mistaken for tarantulas.
Wolf spiders are not known to be aggressive but will bite if provoked or threatened. Their bite is not considered dangerous to people but it can be painful (like a bee sting). When disturbed, they will retreat very quickly.
Young wolf spiders hatch from eggs and look like tiny adults. They shed their skin as they grow. Males reach maturity from spring to summer. Mating occurs in autumn and the males die before the winter begins. Females lay eggs soon after mating. They carry their egg sacs in a silk cocoon attached to their abdomen by spinnerets. The spiderlings hatch in June and July and attain only half of their full size by the following winter. After hatching, the spiderlings cling to the mother’s body for about a week before detaching. They too will overwinter and complete their growth the following spring and summer. Female wolf spiders may live for several years. It is common to find females carrying their young spiderlings on their backs during the summer months. They can be a common pest in the fall when they begin to seek shelter from cooling temperatures.
The wolf spider is a solitary creature, preferring to live and hunt alone. Most are wanderers without a permanent home; however some Carolina wolf spiders create deep tubular burrows to live in. While wolf spiders prefer to live outdoors on the ground, they may occasionally wander indoors, where they might be found around doors and windows, and in garages. They may be seen running across the floor when disturbed. To keep spiders out of your home, seal cracks, gaps and other openings. For immediate and long-term control of wolf spiders, physical removal and/or destruction of the individual spider may be the best control.
For further information visit: http://www.ipm.ucdavis.edu/QT/commongardenspiderscard.html