Organic Lettuce Seeds — 'Green Leaf Black Seeded Simpson'

Overview

Lettuce is a cool weather crop. The essential base for most fresh salads, lettuce comes in a range of greens and reds, as well as different head types that offer contrasting leaf shapes and textures between tender and crispy-crunchy. Lettuce contains substantial amounts of vitamins A, C, and B6, as well as thiamin, riboflavin, calcium, and other minerals.

Conditions

For soil, use a fertile well-draining potting mix that’s tailored for vegetables. Lettuce thrives in cooler growing temperatures between 60–65°F, so it is best grown in the early spring or after the summer heat has passed. For the best quality leaves, provide full sun (6 or more hours of direct sunlight) without excessive heat.

Planting

Use our grow calendar tool to find specific dates for your region! Seeds germinate in 5-10 days.

Plant seeds every 3 weeks for a continuous supply of fresh lettuce. 

All of our lettuce varieties are recommended for planting directly outdoors in the garden once the soil is warm enough to be worked. Plant 6 seeds per foot, in rows 12-18" apart. Cover seed lightly, about 1/8", and firm soil gently. Thin to one plant every 8-12" for full-size heads. 

For larger head varieties, seeds can be started indoors in small containers or cell trays approximately 4 weeks before the desired transplant date. Transition outside (harden) for 3-5 days before outdoor transplant. Space 8-12” apart for full-sized heads.

For salad mixes or baby leaf growth, plant seeds in dense 2-4” bands, approximately 60 seeds per foot. 

Pests and Disease

Downy Mildew is one of the most serious diseases of lettuce, especially in late summer plantings. Disease pressure for this and other lettuce diseases may be mitigated by increasing row spacing, orienting rows for optimum air flow, using drip irrigation, and practicing crop rotations. Lettuce Mosaic Virus (LMV) is transmitted by many species of aphids. Encourage beneficial insect activity by planting “barrier plants” such as alyssum, chives, or garlic nearby to suppress aphid populations. Provide adequate Calcium and avoid excessive Nitrogen and Phosphorus to prevent tipburn.

Harvest

Cut lettuce heads at the base when they reach full size. If left to grow for too long they will start to elongate and go to seed, which turns them bitter. Wash in cold water and store in the refrigerator to crisp up. 

Loose leaf types can be harvested gradually by pulling off a few outer leaves at a time, leaving the central heart to continue growing to maturity.

Baby leaf varieties can be harvested starting from 3 weeks after planting. Clip leaves carefully, and keep roots in-ground as new leaves will grow from cut stems. Harvest as needed and use quickly for best taste and texture. 

Have your harvested lettuce leaves wilted? Put the leaves in a bowl of cold water with ice cubes and soak for about 15 minutes for them to rehydrate.