Lettuce Growing and Harvesting Information
| Temperature | |
| Germination | 40-80 F |
| For Growth | 60-65 F |
| Soil and Water | |
| Fertilizer - Heavy feeder, use compost | |
| Side-dressing - Apply balanced fertilizer | |
| pH | 6.0-7.5 |
| Water | average |
| Measurements | |
| Planting depth | 1/4 - 1/2" |
| Root depth | 18-36", taproot to 5' |
| Height | 6-12" |
| Width | 6-12" |
| Space between plants | |
| In beds | |
| - Head | 10-12" |
| - Leaf | 6-8" |
| - Romaine | 10" |
| In rows | 12-14" |
| Space between rows | 14" |
| Average plants per person | 10-12 |
| Harvest | |
| For leaf lettuce, start picking the leaves when there is at least 5-6 mature leaves of usable size. Usable size means about 2" long for baby lettuce, and 5-6" long for more mature lettuce. Keep picking until a seed stalk appears or the leaves become bitter. For head lettuce, when the head feels firm and mature, simply cut it off at the soil surface. Harvest all lettuce in early morning for the maximum carotene and best taste. refrigerate immediately. | |
| First Seed starting Date: 25-46 days before last frost date | |
| Last Seed Starting Date: 92-127 Days before first frost date (head) | |
| Last Seed Starting Date: 77-97 Days before first frost date (leaf) | |
| Last Seed Starting Date: 87-112 Days before first frost date (romaine) | |
| Companions | |
| Companions: Beet (to head lettuce); all brassicas (except broccoli), carrot, cucumber, onion family, pole lima bean, strawberry | |
| Incompatibles: Nothing conclusive | |
Where to grow Lettuce
Practically anywhere. Since it is a cool-season vegetable,
with an ideal temperature of 50-60 degrees, lettuce does poorly in
hot weather, and is tolerant to some frost and light freezes.
The leafy types mature quickly and are more suited for warm
climates. Cos is also more heat tolerant.
Reccomended Varieties of Lettuce
There are two basic categories of lettuce: heading
and non-heading. Head lettuces include crisphead (e.g..
Iceberg) and butterhead (e.g.. Bibb and Boston). Nonhead
lettuces include leaf and romaine (also known as cos). For
head lettuce, one source suggests that you strip transplants of
outer leaves to help the inner leaves head up better. This
has not been confirmed, so treat it as experimental for now.
Head lettuces tend to be milder in flavor but are more difficult to
grow.
Recommended varieties:
Head - Fulton; Ithaca; Big Boston.
Bibb - Buttercrunch; Summer Bibb.
Leaf - Black Seeded Simpson; Salad Bowl; Ruby; Oak Leaf;
Slobolt; Grand Rapids.
Cos or Romaine - Parris Island.
Soil for Lettuce
Lettuce doesn't do well in very acidic soils, and some say the pH shouldn't be lower than 6.5. A rich, muck "celery" soil is excellent for lettuce, but the crop will also do well in average garden soil. The best crops are grown in soil that is deeply enriched with well-rotted manure and is well-fertilized before planting, especially with high nitrogen--leaf-stimulating--fertilizers such as 10-8-4, cottonseed meal, or blood meal.
Planting Lettuce
When - Early spring in regions where summers are hot, and
again in late summer for all crop. Head lettuce, especially,
requires a long, cool growing season, and seed is usually started 6
weeks ahead. Transplants can be purchased. When sowing
leaf lettuce, rows can be made by mixing several varieties. As
the crop wanes, a second sowing can be made or else it can wait
until late summer, for fall. During hot weather, sow lettuce
in partial shade, as it doesn't do well in the heat, and use
heat-resistant varieties.
How - Seed should be sown thinly in rows 1 foot apart; for
leaf types, thin plants to 2-3 inches apart, then thin again by
pulling every other plant when half grown. This will encourage
thickly developed plants. For head, Bibb, and cos types, space
rows 18 inches apart, plants 8-10 inches apart. Closer spacing
results in smaller heads, which may be preferable for small
families. Specialty growers are spacing lettuce very close for
selling baby lettuces, a rapidly growing produce market.
How Lettuce Grows:
Lettuce is about 95 percent water. It develops rapidly if the growing season is cool and moist. Head lettuce forms a tight, compact cabbage head from a dense rosette of leaves. Bibb develops a loose head of broad succulent leaves with superb flavor. Leaf lettuce has loose crispy or curly leaves that develop from a basal growing point. Cos and romaine also develop from a basal growing point, but the leaves are oblong and grow upright.
Cultivating Lettuce:
Since cultivation is difficult with these shallow-rooted plants, a mulch of grass clippings, salt hay, clean straw, or the like, will keep the weeds out and the growing soil moist and cool. Watering is essential if rainfall is scant. The plants need almost constantly moist ground.0
| Storage Requirements | ||
| Lettuce does not store well for long periods and is best eaten fresh. | ||
| Fresh | ||
| Temperature | Humidity | Storage Life |
| 32-40 F | 80-90% | 1 month |
| 32F | 98-100% | 2-3 weeks |
Harvesting Lettuce:
Head - 2 months. Pull the entire plant from the soil.
Bibb - 6-8 weeks. Pull the entire plant from the
soil.
Leaf - 6 weeks and continually, since these are "cut and
come again" plants. Cut the outer leaves when mature to allow
center leaves to develop.
Cos - 2 months. Pull the entire plant.
Lettuce Pests:
Aphids - Either grow nasturtiums near the lettuce, or if
there is a heavy population , use rotenone or pyrethrum. Most
minor infestations can simply be washed off before the plants are
eaten.
Slugs - Place beer in shallow pans at dusk and empty the
drowned slugs as they feed and they will "dissolve."
Lettuce Diseases:
Most of the blights and troubles have been eliminated through plant breeding and hybrid vigor.
