Pea plants are a popular garden addition, known for their sweet, tender pods. While they thrive in cooler temperatures, they are sensitive to frost. Protecting pea plants from cold snaps is essential for a successful harvest. This guide offers practical steps for frost protection and post-frost care.
Why Frost Harms Pea Plants
Frost damages pea plants at a cellular level. When temperatures drop below freezing, water within plant cells crystallizes, forming sharp ice shards. These ice crystals expand and rupture cell walls, causing irreversible tissue damage. Young shoots and tender leaves, with their higher water content, are especially susceptible.
This cellular damage disrupts the plant’s ability to transport water and nutrients, effectively shutting down its physiological processes. Affected parts wilt, blacken, and become mushy. Sustained freezing temperatures can lead to widespread tissue death, which can be fatal to the entire plant.
Immediate Strategies for Frost Protection
Implementing protective measures before a predicted frost can significantly reduce damage to your pea plants. Covering plants with lightweight materials like row covers, old sheets, blankets, or plastic sheeting creates an insulating barrier. Ensure covers do not directly touch the foliage, as cold can transfer through the material; use stakes or hoops to maintain an air gap.
Secure covers firmly to the ground to prevent wind displacement and trap radiant heat from the soil, keeping the air around plants slightly above freezing. For individual plants or small groupings, inverted buckets or cloches offer quick, localized protection.
Watering the soil thoroughly before a frost also provides a layer of protection. Water retains heat more effectively than dry soil. As temperatures drop, moist soil slowly releases stored heat, warming the surrounding air and mitigating freezing impact on roots and lower stems.
For added warmth, temporary heat sources can be used under covers. Stringing old incandescent holiday lights (not LED) through the canopy provides gentle radiant heat. Dark-colored plastic jugs filled with warm water, placed among plants before nightfall, absorb solar heat during the day and release it overnight.
Post-Frost Care for Pea Plants
After a frost, it is best to wait until morning, allowing temperatures to rise and any frozen tissues to thaw naturally, before assessing the damage. This waiting period helps reveal the true extent of injury, as some seemingly damaged parts may recover. Once thawed, you can clearly identify any blackened, limp, or mushy foliage that has succumbed to the cold.
Carefully prune away any damaged portions of the plant using clean, sharp shears. Removing these dead or dying parts can help the plant redirect its energy towards new growth and prevent potential disease issues. Be gentle and avoid unnecessary disturbance to healthy tissues.
Continue to provide regular watering and care to your pea plants as they recover. Ensuring adequate moisture and nutrients will support the plant’s efforts to produce new shoots and leaves. With proper post-frost attention, pea plants often recover and continue their growth cycle.