How to Plant Your Edible Garden
Take care to plan out your edible garden before diving in. Consider any theme or general approach to your garden, how your plants will be organized, how to invite pollinators, and whether you'll be planting your crops from seeds or starts. Most importantly, be sure you plant at the correct time. Here's how to manage it all.
APPROACH: Getting started
There are many ways to grow edibles, whether incorporated in the ornamental landscape or in a separate area of the garden.
Edible landscape
Use edibles in place of ornamentals in your landscape or integrate them within existing ornamentals. Blueberries and artichokes are beautiful ornamental shrubs. Blackberries, asparagus and raspberries make a nice hedgerow. Herbs make a lovely border.
Theme gardens
Edible flowers, ratatouille or salad niçoise garden, tea or salsa garden, etc.
Planting space & relative square foot value
• If space is tight: High-yield per square foot plants
Herbs, parsley, carrots, and beets provide the greatest yield per square foot. In other words, you get the most produce from the smallest amount of space. If space is tight, these edibles are good choices.
• If space is not an issue: Low-yield per square foot plants
Winter squash, sweet corn, watermelon. and pumpkin have the least yield per square foot. Grow these if space is not an issue or if you don't mind edible vines creeping through your ornamental beds.
Others crops are somewhere in between.
GROUPING PLANTS: How to organize your edible garden
Use the guidelines below to create a planting plan for your edible garden.
MOST IMPORTANT: Hydrozones and plant spacing
Hydrozones
Place edibles with similar water needs together. Plants with similar root depth have similar water requirements.
• Most edible plants are shallow rooting (approximately 12 inches or less). Examples include lettuce, arugula, basil, chives, garlic, kale, mustard greens, and some carrots.
• Deeply rooting plants include artichokes, asparagus, parsnips, rhubarb and tomatoes.
• Most annuals need one inch of water per week and up to two inches in hot weather. Learn how to calculate an inch of water.
• Tomatoes need less water after fruit has set.
• Perennial herbs need less water after they're established.
Plant spacing
Place crops according to size at maturity or according to spacing suggestions. Vegetables harvested before full maturity, such as beets or greens, may be placed more closely.
Plant placement
Consider:
• Shade: Place taller plants on the north side of your bed/garden so they will not shade shorter plants. Plant crops that enjoy light shade, such as lettuce, in the shadow of taller plants.
• Ease of access: Group shorter plants near the front of beds so they're easy to reach.
Rotation
Group plant families together for easier seasonal crop rotation.
Frost-sensitive plants
Place frost-sensitive plants such as peas and citrus in protected areas near a structure, fence, or in an otherwise protected spot. Use cold frames to get seedlings started outdoors.
Perennials
If space allows, grow perennials such as asparagus, artichokes, berries, herbs, fruit trees, sunchokes, and walking collards in separate beds or containers.
POLLINATORS: how to attract them
If not for pollination, our food gardens would be lovely, under-productive patches of green. In fact, pollination accounts for one out of every three bites of food we eat. That said, the need for pollination varies by crop:
| Require no pollination | Carrots, kale, and other edibles, which we eat before pollination occurs |
| Self-pollinating | Beans, peas and tomatoes |
| Wind-pollinated | Beets, chard, and corn |
| Require pollination | Brassicas, cucumbers, melons, okra, pumpkins, squash and many fruit trees Pollinated by hummingbirds, bees and other insects, and in their absence, humans! |
Use our lists of Plants for Bees, Hummingbirds, and Butterflies. These plants are easy to grow, bloom heavily, and are good company for edible crops. They create spots of color, texture, and scent. The result is so much more than an edible garden. It is a resilient, sustainable, fascinating ecosystem. Learn more about habitat gardening, pollination, and pollinators.
KNOW YOUR SOIL TEMPERATURE: Guidelines for warm & cool season crops
Edible crops are not only sensitive to air temperatures; they are also sensitive to soil temperatures. Whether planting seeds or starts make sure soil temperature is adequate:
Warm season crops need soil temperature at 60 to 65 degrees.
Cool season crops need soil temperature at about 40 degrees.
How to take your soil's temperature
• Use an instant read thermometer, the kind used in the kitchen. Insert it into the soil about 3 inches deep.
• The best time to check soil temperature prior to planting seeds and seedlings is in the morning because this will be the coolest soil temperature of the day. If you want to know the warmest soil temperature, check the soil in late afternoon.
To raise soil temperature
• Cover the bed for a few days with a dark material, such as heavy weed cloth.
PLANTING: SEEDS OR STARTS?
When planting your garden, you have a choice between planting seeds or starts. Most gardens include plants propagated from both seeds and starts.
WHAT ARE STARTS?
Starts are plants you buy at the nursery or grow yourself from seed.
HOW TO PLANT STARTS • Harden off: If you have grown your own starts, be sure to harden them off for about a week before planting in the garden by leaving the plants outside each day for longer and longer periods of time but bringing them in at night. Starts purchased from a nursery are already hardened off. |
SEEDS: Growing your own starts
Follow directions on seed packets and decide if you are going to start the seed indoors in a container or direct sow into the garden.
Benefits of growing edibles from seed:
• Variety: Starting with seed reveals a world of vegetables that you will never find in the market or nursery.
• Cost: Growing from seed is less expensive than buying starts.
• Sharing: You can exchange different varieties with friends.
• Disease resistance: Growing from seed reduces the risk of introducing diseases into your garden.
• More control over timing: This can help when rotating crops or doing succession planting.
| HOW TO SOW SEEDS INDOORS or in a cold frame outdoors • Begin 3-6 weeks before planting into the garden. • Use a fine textured seeding mix • Use any kind of container that is at least 2 inches deep and drains. • Fill the container or flat with seeding mix. • Level out. • Place seeds more densely than recommended on the seed packet, as some will not germinate. • Once the seedlings are about 1-inch high, thin with scissors, giving each seedling 2 inches of space all around. • When the seedling has at least 2-3 true leaves, feed with fish emulsion diluted to half the standard strength. (Seeding mix does not usually contain nutrients since the seed uses nutrients stored in the seed.) • Transplant in the spring after danger of frost or according to the recommended planting time. |
Seed types to sow indoors or in a cold frame:
• Smaller seeds are usually started in a flat in a protected environment (indoors or out) and transplanted after a full-set of leaves has formed and the plants have been hardened off (gradually exposed to outdoor elements). An exception are small seeds that mature quickly, such as lettuce and arugula, which may be directly sown into the garden.
• Large seeds such as beans, peas or squash may be started indoors and transplanted to provide a head start on the growing season.
• Medium size seeds such as those for eggplants, tomatoes and peppers are started indoors and transplanted outdoors.
| HOW TO SOW SEEDS DIRECTLY into the garden • Plant large seeds the depth recommended on the seed packet (usually about the length of the seed). • Scatter small seeds on the surface of the bed, then top lightly with soil. • Thin with scissors to recommended planting spacing when seedlings are 1 to 2 inches tall. • Cover with tulle to protect from birds. |
Edible crops to sow directly by seed into the garden:
• Large seeds: beans, pumpkins, squash, peas
• Root crops: beets, carrots, parsnips, radishes, turnips
• Quickly maturing seeds: braising mix, lettuce, microgreens
TIMING: when should you start growing?
In the edible garden, this is a critical question that could mean the difference between success and failure. Check online for information on specific plants, or use our planting calendar and our grow sheets as a guide.
BACK TO EDIBLES
> What Edible Gardens Need
> Best Choices for Marin
> How to Prepare
> How to Plant
> Edibles in Containers
> Planting Calendar
> Grow & Care Sheets for Vegetables, Herbs & Fruits
> Tips & Techniques
> How to Maintain
> Fruit Trees
> Top 20 Edible Garden Problems
> Cover Crops & Soil Enhancements in the Off-season
> Conserving Water
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Visit our EDIBLE DEMO GARDEN at IVC Organic Farm & Garden
August 2022: Managing Pests in the Organic Garden
Cooperation with nature is a guiding principle of organic gardening and this includes the management of unwanted bugs and critters. Organic gardeners steer clear of toxic pesticides and instead implement integrated pest management strategies starting with those least harmful to the environment. This is earth-friendly gardening in practice.
Integrated Pest Management (IPM)
IPM is based on the understanding that the most effective long-term way to manage pests is to use a combination of methods that minimize risks to people and the environment. These approaches fall into the following categories.
- Biological controls – Most of the creatures found in gardens are not pests and are benign or beneficial. Biological controls engage natural enemies in pest management. Good bugs reduce pest damage by eating the bad bugs. Using ladybugs to reduce aphids is only one of many examples of the action of natural enemies. Birds, lizards, and insects, such as praying mantis, are also beneficials but are not as specialized.
- Cultural controls – Good garden practices such as nurturing the soil, clearing out debris, properly managing irrigation, and removing infected plants can also deter pests. Rotating crops reduces the chance that pests will become established in a certain location. Companion plantings can provide protection by luring pests away from their favorite food sources.
- Mechanical and Physical Controls – Blocking pests from access to garden plants is the most effective way to prevent damage. In the Edible Garden, where gophers are abundant, plants are protected with underground wire mesh. The lost sunflowers were in an area of the garden without gopher protection. Row covers effectively keep out both birds and insects but are not useful for plants with flowers requiring pollination.
Frequent monitoring for signs of pests is key to reducing crop damage. Many times, a hard spray of water will wash off sucking insects such as aphids and their ant companions. Hand removal is always an option for larger nuisances such as cucumber beetles, slugs, and hornworms.
- Chemical controls – The use of selective, less toxic pesticides can be included among IPM strategies but only when other methods have been ineffective. Chemicals are rarely used to control pests in the Edible Garden. As part of the Indian Valley Organic Farm and Garden, the Edible Demo Garden must adhere to Marin Organic Certified Agriculture standards in terms of chemical use. Only approved non-synthetic pesticides can be used.
More information on controlling pests is available on this website at: http://marinmg.ucanr.edu/PROBLEMS/
Detailed information on IPM and links to specific pest problems can be found at: http://ipm.ucanr.edu/index.html
July 2022: Plant Partners
Companion Planting
Companion planting as a gardening technique has been practiced for generations, based on discoveries about how combining two or more plant species together can provide mutual advantages and enhance growth and production. The classic example is the Native American “three sisters” plantings combining corn, beans, and squash. Ideally, the corn provides structure to support the pole beans and the squash spreads out underneath the other plants. The best plant companions do more than just grow well side-by-side, they interact and form partnerships which benefit one or more of them.
How Plant Partnerships Work
Many old beliefs about which plants make good companions are based on folklore or trial and error rather than sound science. Fortunately, there are now numerous credible studies and controlled experiments that are helping to explain the ecosystems that enable edible garden plants to thrive. There are many ways in which one plant can influence another by either enhancing conditions for growth or increasing protection against threats.
- Enhancing conditions for growth
Certain plant partners can improve soil composition by breaking up heavy soil or assisting in nitrogen transfer. Companion plants can increase the number and diversity of pollinators leading to higher yields. A sturdy upright plant can serve as a living trellis to support a vine crop. Plant partners can also promote the health of beneficial soil-dwelling organisms and assist in the movement of nutrients within the soil.
- Increasing protection against threats
Probably the most common goal of companion planting is to manage pest insects. Studies have demonstrated that some plant partners are able to confuse pests and make it harder for them to find their preferred host plant on which to feed or lay eggs. The chemical and visual cues on which the insect pests rely are masked by the companion plant. Weed management without herbicides can be another plant partnership benefit. Some plants produce chemical compounds that inhibit weed growth and others act as living mulch. Finally, there is evidence that certain plant diseases can be suppressed through plant partnerships.
A Few Examples of Tested Plant Partners
- Peas and Lettuce – Both are cool-season crops with different growth structures. The peas climb while the lettuce stays low. The peas benefit the lettuce by shading them in warmer weather and providing nitrogen via the mycorrhizal network.
- Pak Choi or Radish and Eggplant, Peppers, and Tomatoes – Pak choi and radish are favorites of flea beetles. Planting radish or pak choi a few weeks ahead of the other vegetable crop can serve to trap the flea beetles and reduce damage to other vegetables.
- Tomatoes and Basil – This combination can work in the garden as well as in the kitchen. The basil serves to mask the tomato plants from thrips, small sucking insects that can damage tomato plants and fruit.
- Cosmos and Cabbage - Combining members of the aster family (which includes coreopsis, yarrow, zinnias, and marigolds) with cabbage, broccoli, cauliflower, kale, and other members of the cabbage family has been shown to reduce aphid numbers by attracting beneficial, aphid-eating insects.
Diversification is Key
Plant partnerships work because they support diversity in the garden and contribute to a healthy ecosystem. Not all plant partnerships work as planned in home gardens. There can be unwanted competition, the timing might be off, or the location might not be right. But even when there seems to be no measurable success, the hidden benefits of an environmentally friendly garden can be appreciated.
More information on growing edibles is available on this website at http://marinmg.ucanr.edu/EDIBLES/.
