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Hardening Off Seedlings on a Screened Porch

A roofed, screened porch does NOT protect from frost. Frost kills tomatoes/peppers even under cover. Only a cold frame adds ~10°F protection. Harden off after last frost date: 1 week gradual exposure.

Safe Timeline for Upstate NY

Last frost ~May 1 (can be May 30).
Start seeds 6–8 weeks before last frost.
Keep indoors under lights (3" above, 14 hrs/day) until frost-free.
Then harden off 7 days.

Peppers: full sun. Cantaloupes: need heat, space, and pollinators. Lettuce heads need cool weather to form—heat prevents heading.

Growing Vegetables: Early Winterizing in Massachusetts: Mulch Depth and Temperature Spikes; Protecting Pygmy Sundews and Drosera Regia from Frost in Zone 9; Venus Flytrap Seed Germination: Pure Peat Moss Method; General Post-Frost Plant Care: Trimming, Watering, and Waiting; Frost-Damaged Palms and Bird of Paradise: Pruning and Fertilizing Guide; Preventing Leggy Seedlings: Light, Pinching, and Hardening Off; Lifting Tender Bulbs Before Frost: Safe for Calla, Canna, Dahlia; Overwintering Impatiens, Geraniums, and Begonias Indoors: Propagation by Water Cuttings and Pest Prevention; Thinning Overcrowded Tomato Seedlings; Saving and Starting Jalapeño Seeds at Home

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