How to Plant a Raised Garden Bed
Planning a raised bed garden requires an understanding of unique space needs for different crops, how roots function under the soil, the finite amount of nutrients available in soil, compatible and incompatible crops, and pollination.
At Noyes Park, gardeners have about 22-24 feet of growing space per plot. This is enough to quite a variety of herbs, fruits, vegetables, and flowers. However, gardeners will need to measure, plan carefully, and select crops that are compatible, not invasive, not too greedy (in terms of nutrients), and not too tall (under 5-feet).
There is a lot of information on the Internet about crop spacing. However, there is some wiggle room when growing in raised beds. For maximum harvest, you should not crowd. However, you can space a little closer than some crops “officially” need.
Planning Your Raised Bed Grid
First, get a loose idea of what you want to grow. Don’t forget to grow flowers with nutrient-rich pollen for your pollinators. Flowers can be grown along the edges.
After you have a few crops in mind, research their spacing needs.
Draw out a rectangular box that represents your plot, to scale. Assign a square foot to each square, like the visual below. Now that you have a grid, let’s select your crops!
Selecting Crops for Your Raised Bed Garden
Considerations
Avoid Invasive Species: Before even starting the selection process, be informed that invasive species are a big no-no in D.C. community gardens. These plants can outcompete native species and disrupt the ecosystem.
Attract Pollinators: Consider planting pollinator-friendly flowers along the edges of your bed. Not only do they beautify the space, but they also attract bees and butterflies, which aid in pollination.
Space Needs: It's essential to be mindful of the space each plant requires, both above and below the soil. Different plants have roots that spread to varying degrees and have distinct nutritional needs. For instance, while corn can significantly deplete soil nitrogen, tomatoes and eggplants require a balance of nitrogen, potassium, and phosphorous.
Root Functions: Though some root competition is natural, providing consistent, rich, organic nutrients ensures that plants thrive without choking each other out.
Compatibility: Some plants just don’t get along. While tomatoes and marigolds make good bedfellows, tomatoes and corn don't. Ensure you consult a compatibility chart when planning your planting layout.
Beware of Cross-Pollination: While a certain degree of cross-pollination is unavoidable, closely planting species from the same family can lead to undesirable hybrids. Always research potential cross-pollination threats for your chosen crops.
Example raised bed layout
With countless plant varieties available, choosing what to grow can be daunting - but fun! A good strategy is to mix familiar crops with some unique ones. Here’s a sample crop list for a 4’ x 8’ raised bed:
Flowers (Eastern Edges):
Calendula
Marigolds
Goldenrod
Herbs (Eastern Corners & Edges):
(2) Sweet Basil
(1) Rosemary bush
Fruits (Central Bed):
(2) BonBon squash
(2) Manganji pepper
(2) Big Rainbow tomato
(2) Aswad eggplant
Vegetables (Towards the Eastern Edge):
(2) Lacinato kale
(12) Merlo Nero spinach
Plant shorter crops, like herbs and certain vegetables, on the Eastern side of your bed to avoid shading from taller plants. For crops that climb, such as certain varieties of tomatoes, use stakes and twine to encourage vertical growth.
What Plants Grow Well in Washington, DC?
In addition to things like spacing, plant height, compatibility, etc., there are few more factors you should consider when planning your garden. Washington D.C. is quite diverse for gardening, which makes for a fun growing season. You’ll likely want to grow a mix of things that ripen between June and October.
Certain crops will need an entire summer to grow and ripen (pumpkin, turmeric), while others will start to ripen as early as late June (some tomatoes & leafy greens). Before finalizing your choices, consider the following:
Maturity Timeline
Once sown or transplanted, how long does this crop take to provide ripe fruit? If you choose lots of crops that don’t ripen until September, you’ll spend the summer watering and maintaining, but no harvesting. That is no fun, especially for new gardeners.
Heat/Cold Hardiness
Crops such as kale, spinach and broccoli are popular choices because they’re meal staples. However, these are classically cool-weather crops. If you want to grow them during summer, be sure to choose a heat-hardy cultivar, or your crop will be bittertasting, and may fail altogether. For winter gardening, the opposite applies. Verify that a crop is cold-hardy in Zone 7B before attempting to usher it through a D.C. winter.
First, 2nd or 3rd Year Fruit
Some crops, like blueberry bushes or strawberry plants, require 1-3 winters in the ground before they begin producing fruit. To avoid being disappointed by a lack of fruit, make sure your crop will produce its first year.
