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Organic Lettuce - Growing and Seed Saving Info

PLANTING INFO:
Days to maturity are from direct seeding in spring conditions, subtract 10-14 days if transplanting, subtract 7-10 days if planting in summer conditions, add 20 days if planting late summer-fall; Seeding depth: 1/8�, seeds require minimum amount of light for germination. Babyleaf- Seeding rate: ~60 seeds/ft, in 2� bands; Row spacing: �� between bands, 16 rows/36� bed.

Full Size- Seeding rate: 3 seeds every 8-10�, Plant spacing: 8-12�; Row spacing: 12-18� or 3 rows/36� bed, 5� centers.

CULTURAL INFO:
Lettuce is cool season annual that can be seeded in the spring as soon as the soil can be worked. In certain areas, lettuce can be grown throughout the summer by choosing varieties which are heat tolerant; however, many lettuce varieties have difficulty germinating in soils above 75�F. Start transplants 3-4 weeks before setting out. Sow seeds 4 per inch in flats or small-cell plug trays, barely covering with fine soil. If sowing into flats, transplant 2 weeks later into plug trays, pots, or into another flat at 1-2� apart. Harden off seedlings by reducing water and temperature for 2-3 days before transplanting. Cut lettuce holds best when harvested in the morning and cooled rapidly. For salad mix or baby leaf production, harvest individual leaves when they reach desired size, or cut evenly across the bed making sure to stay above the growing tip. For a continuous harvest, sow lettuce every 3 weeks. Different lettuce varieties are adapted for a wide range of temperature conditions; choose heat tolerant, bold-resistant varieties (such as Batavian types) for summer plantings and cold tolerant varieties to withstand light late-season frosts.

DISEASE & PESTS:
The primary lettuce diseases are downy mildew (Bremia lactucae), drop (Sclerotinia sclerotiorum, also called white mold), damping-off (caused by a number of soil-borne fungi), bottom rot (Rhizoctonia solani), and lettuce mosaic virus (LMV). Other than LMV, which is highly seed-borne, the other diseases are best prevented by production practices that maximize airflow around heads to stimulate rapid drying. Many varieties have resistances disease.

RESISTANCE KEY: DM:
Downy Mildew (race specified, if known), TB: Tip Burn, WM: White Mold, BHR: Bacterial Head Rot, BR: Bottom Rot, HS: Heat Stress, LMV: Lettuce Mosaic Virus, APH: Aphids, MTO-10, MTO-30: 10,000 or 30,000 seeds were tested for the presence of Lettuce Mosaic Virus (LMV) and no LMV found. A disease-free test does not guarantee a seed lot to be disease-free, only that no pathogen was detected in sample.

SEED SPECS:
24,000 seeds/oz avg. M= 1,000, MM=1,000,000

SEEDING RATES:
Baby Leaf - 96M seeds/100� bed (~ 4 oz), 960M seeds/1,000� bed (2.5 lbs), 7.7MM seeds/acre (~20 lbs), using ~960 seeds/ft, 16 rows/bed, 36� beds, 6� row centers. Full Size - 360 plants/100� beds (~1/32 oz), 3,600 plants/1,000� beds (1 oz), using 10� spacing, 3 rows/36� bed, 5� center beds. 31M plants/acre (~2 oz), using 10� plant spacing. These specifications are meant to be general guidelines for the particular application as noted. They can be loosely applied across the board for lettuces/mixes found in this section.

SEED PELLETING INFO:
Some varieties of lettuce are sold as pelleted seed. Read more information about organic seed pelleting.

SEED SAVING INSTRUCTIONS:
Self-pollinated. Lettuce varieties will not cross pollinate with each other even at short distances, but beware of any wild lettuce which can cross with lettuce. Allow plants to "bolt" and eventually flower. Under wet conditions lettuce plants may need to be covered with a rain cover or grown in a greenhouse to prevent fungus from infecting the plant and seed heads. Carefully shake the seedheads into a paper bag to allow the mature seeds to be collected while leaving the immature seeds and flowers to keep growing. Gather every few days until no more seeds remain. Also, you can simply harvest the entire plant when about half of the seeds are mature and allow the rest to mature inside by standing up the plants in a box and on a cloth or tarp. Use an 1/8" screen to help with cleaning. Lettuce seed can remain viable for 3 years under cool and dry storage conditions.