Peas are a rewarding, cool-season crop, and planting them in a raised garden bed provides an optimal environment. Raised beds are beneficial because the soil warms up faster in the spring, allowing for earlier planting. The contained structure also ensures better drainage, preventing the soggy soil conditions that peas dislike and which can lead to root rot. This system provides a defined space that makes integrating support structures and harvesting easier.
Pre-Planting Preparation
The first step is choosing the right variety for your space and desired harvest. Pea varieties fall into two main growth habits: bush or dwarf types (18 to 30 inches tall, minimal support), and vining or pole types (4 to 6 feet, mandatory trellising). You must also decide between shelling peas, snap peas, or snow peas, selecting a cultivar appropriate for your raised bed’s height and support structure.
Peas thrive in fertile, well-draining loamy soil, easily achieved in a raised bed. The ideal soil pH should be slightly acidic to neutral (6.0 to 7.5). While peas are nitrogen-fixing legumes, applying a specialized inoculant to the seeds before planting is highly recommended.
The inoculant contains Rhizobium leguminosarum, a beneficial bacterium that forms nodules on the pea roots, enhancing their ability to fix nitrogen. This results in healthier plants and improved yields. To apply it, simply moisten the pea seeds slightly with non-chlorinated water and toss them with the powdered inoculant until coated. Plant the inoculated seeds immediately, as the bacteria are living and should not be allowed to dry out.
The Planting Process
Peas should be planted in early spring as soon as the soil is workable, which often coincides with a soil temperature of at least 10°C (50°F). Because raised beds offer limited space, employing intensive planting methods maximizes the yield within the small footprint. Instead of long, single-file rows, you can utilize block planting, treating the raised bed surface as a continuous planting area.
Sow the pea seeds approximately 1 to 2 inches deep into the prepared soil. For intensive planting, seeds should be spaced about 2 to 3 inches apart in all directions, or about eight seeds per square foot. This close spacing allows the mature plants to shade the soil, keeping it cool and moist, and suppressing weed growth.
You can speed up germination by soaking the pea seeds in lukewarm water overnight immediately before inoculation and planting. Once the seeds are covered with soil, a thorough initial watering is necessary to settle the soil and initiate germination. The soil must be kept consistently moist until the seedlings emerge, which typically occurs within seven to ten days.
Essential Support and Initial Care
Since most pea varieties benefit from some form of vertical support, it is important to install the trellising system at the time of planting, especially for vining types. Waiting until the plants begin to climb risks disturbing the shallow root systems when installing stakes or posts. Suitable supports for raised beds include simple A-frame trellises made from bamboo or conduit, netting strung between posts, or a sturdy cattle panel arching over the bed.
The climbing plants use small, grasping tendrils to secure themselves. The support structure prevents the vines from sprawling onto the soil, which improves air circulation and reduces the risk of fungal diseases.
Once the seeds have sprouted, they may be vulnerable to early spring conditions and pests. If a sudden, hard frost is predicted, you can protect the young seedlings by covering the raised bed with a floating row cover or a simple blanket, which traps warmth and creates a microclimate.
Protecting the young plants from common garden pests is also a concern, as mice and birds may pull up the seedlings to eat the buried seed. Temporary barriers like a cage made from fine hardware cloth or covering the bed with a thin row cover until the plants are established will deter most animals.
Due to the initial richness of raised bed soil and the nitrogen fixed by the Rhizobium bacteria, peas usually require little to no supplemental fertilizer. If the soil is particularly lean, incorporate compost or a low-nitrogen fertilizer rich in phosphorus and potassium before planting. This supports root and flower development, rather than excessive foliage growth.