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Lettuce Growing Problems: Troubleshooting

Lettuce problems
Lettuce problems: Lettuce that is crowded or grown in poor soil will be tough and bitter tasting.

Most varieties of lettuce require cool weather or slight shading for best growth. Grow lettuce in the cool part of the year, when temperatures range in the 50s and 60sF. You can plant lettuce as soon as the ground can be worked in spring. Grow leafy varieties where the weather is warmer.

Lettuce grows well in average, but loose and well-drained soil. Don’t crowd lettuce; let it leaf out and grow steadily and quickly for best flavor. Lettuce that is crowded or grown in poor soil will be tough and bitter tasting.

For lettuce growing tips see Lettuce Growing Success Tips at the bottom of this post and How to Grow Lettuce.

Here are common lettuce growing problems with cures and controls:

• Seed planted in mid summer or warm weather fails to germinate. Temperatures are too high. Lettuce seed has a germination rate of 99 percent at 77°F; the germination rate drops to 87 percent 86°F. Use an organic mulch to reduce soil temperature. Plant varieties that tolerate warm soil temperatures: Black Seeded Simpson, Progress, Great Lakes, Imperial 615.

• Seedlings wilt and collapse with dark water-soaked stems as soon as they appear. Damping off is a fungus that lives in the soil, particularly where humidity is high. Do not plant in cold, moist soil. Make sure soil is well drained.

• Seedlings uprooted; leaves torn. Birds pull up seedlings to feed on seed. Cover seedlings with bird block or floating row covers until established.

• Young stems chewed. Young earwigs feed on plant shoots and eat holes in foliage. Most often the damage is tolerable and the infestation is light. Heavy infestation use traps of rolled wet paper or old flowerpots stuffed with paper to catch earwigs at night. Dump them in soapy water. Keep garden free of plant debris. Spray with hot pepper and garlic repellent.

• Leaves are distorted or curled under with small shiny specks. Aphids are tiny, oval, and yellowish to greenish pear-shaped insects that colonize on the undersides of leaves. They leave behind sticky excrement called honeydew which can turn into a black sooty mold. Blast aphids away with water from hose. Use insecticidal soap. Mulch with aluminum foil which will disorient aphids.

• Leaf margins appear scorched and wilted. Leafhoppers are green, brown, or yellow bugs to ⅓-inch long with wedge-shaped wings. They suck the juices from plants. Use insecticidal soap. Cover plants with floating row covers to exclude leafhoppers. Use Sevin, pyrethrum, rotenone.

• Trails of silver slime on leaves; leave eaten. Snails and slugs feed on leaves. Reduce hiding places by keeping garden free of debris. Handpick from under board set in garden as shelter-trap. Use a shallow dish of beer with lip at ground level to attract and drown snails and slugs.

• Small ragged holes eaten in leaves. Cabbage looper is a light green caterpillar with yellow stripes running down the back; loops as it walks. Keep garden clean of weeds and debris where adult brownish night-flying moth can lay eggs. Cover plants with spun polyester to exclude moths. Pick loppers off by hand. Use Bacillus thuringiensis. Dust with Sevin or rotenone.

• Holes in leaves; leaves skeletonized; seedlings eaten. Armyworms or corn earworms:

(1) Armyworms are dark green caterpillars the larvae of a mottled gray moth with a wingspan of 1½ inches. Armyworms mass and eat leaves, stems, and roots of many crops. Handpick caterpillars and destroy. Cultivate after harvest to expose the pupae. Use commercial traps with floral lures.

(2) Corn earworm is a white, green, or red caterpillar with spines to about 1½ inches long. Tomato hornworm is a green caterpillar 3 to 5 inches long with white stripes. These pests will eat holes in leaves and fruit. Handpick and destroy. Spray with Bacillus thuringiensis. Spray with pyrethrum or rotenone.

• Leaf veins are swollen and light yellow; leaves are puckered, ruffled, and brittle. Big vein is a viral disease associated with fine-textured, poorly drained soil. Remove and destroy infected plants. Do not overwater. Keep soil on the dry side. Plant tolerant varieties. Plant when the air temperature is 60°F or greater to lessen the severity of symptoms.

• Leaves faintly mottled; plants are yellow and stunted. Mosaic virus is transmitted by aphids and leafhoppers. There is no control after symptoms occur. Remove infected plants. Control insects. Keep garden free of weeds where insects harbor. Use aluminum mulch to disorient aphids. Plant resistant varieties: Parris Island. Valmaine Cos.

• Plants yellow; dark brown steaks inside stems and larger veins; plant wilts. Fusarium wilt is a soil fungus which infects plant vascular, usually where the soil is warm. If you cut the plant at the base, the stem will be dark reddish brown instead of ivory color. Grow resistant varieties. Rotate crops. Remove and destroy infected plants. Solarize the soil in late spring or summer. Fungicides are not effective.

• Pale yellowish spots develop on upper leaf surfaces; gray-purple powder or mold on leaf undersides. Downy mildew is caused by a fungus. Improve air circulation. Rotate crops. Keep garden free of plant debris. Plant resistant varieties: Arctic King, Big Boston, Salad Bowl, Imperial.

• Sunken, water-soaked spots appear on lower leaves which turn brown and slimy. Rhizoctonia bottom rot is caused by a soilborne fungus. Remove infected plant debris that harbors fungus. Rotate crops. Plant in well-drained area. Solarize the soil in late spring or summer.

• Leaves rot becoming water soaked and turning brownish-black. Bacterial leaf or fungal leaf spot cannot be cured. Plant treated seed. Prune away infected leaves. Keep garden and tools clean. Avoid overhead watering. Plant resistant varieties.

• Stem, lower leaves rot; dense grayish green mold on affected areas. Botrytis gray mold is a fungal disease. Remove and destroy infected plants. Keep weeds out of garden where fungal spores may harbor. Plant in well-drained area.

• Lettuce bolts: flowers and goes to seed before it is ready to eat. Long hot days and warm nights will trigger bolting. Sow lettuce so that it grows and matures in cool weather. Sow lettuce in spring 2 weeks before the last frost or plant in late summer for a fall crop. Plant heat resistant varieties: Great Lakes, Salad Bowl, Slowbolt.

• Leaf tips turn brown and look burned. Sunburn happens when leaves receive full sun in summer. Give plants partial shade in afternoon. Use shade cloth or plant where bed is shaded in afternoon. Plant lettuce in shadows of taller crops.

• Edges of inner head lettuce leaves are brown and rotten; usually not visible form outside of head. Tipburn is a physiological disorder caused by soil calcium deficiency. High temperatures and too much nitrogen can aggravate tipburn injury. Test soil for calcium levels; adjust as necessary. Avoid water stress. Plant lettuce so that it comes to harvest in cool weather.

• Leaves at center of heads are stunted, twisted, narrow, yellowed. Aster yellows is a mycoplasma disease spread by leafhoppers. Remove infected plants. Control leafhopper. Keep the garden free of weeds which can harbor disease. Destroy infected plants. Use Sevin.

• Romaine lettuce does not form heart. Seed was planted too deep; place seed on seedbed and cover with ½ inch of soil.

• Head lettuce does not form head. Plants are crowded. Thin head lettuce to stand from 12 to 14 inches apart.

• Leaves of looseleaf varieties are small and bitter tasting. Plants are crowded. Thin plants to stand from 6 to 10 inches apart.

• Leaf undersides are silver; tiny brown spots on leaves. Smog or air pollution; grow lettuce during cool, clear months.

• Silvery leaves after cold weather. Frost injury; freezing and temperature drops will injure leaves.

 

Lettuce Growing Success Tips:

Planting. Grow lettuce in full sun where the growing season is cool. In very warm to hot growing regions, grow lettuce in partial shade–between taller crops is good. Lettuce requires a minimum of 4 hours of sun each day. Lettuce will grow in average soil, but soil amended with aged compost that is well-drained is optimal. Sow seed directly or set out transplants.

Planting time. Lettuce can be planted in the garden as early as 4 weeks before the last expected frost in spring. For a continuous supply, plant lettuce every couple of weeks until about 4 weeks before the average daytime temperature exceeds 80°F (after that plant lettuce in the shade or sow heat-resistant varieties). Begin sowing lettuce again towards the end of the growing season, about 8 weeks before the first expected frost in fall.

Care. Lettuce is shallow-rooted and requires consistent, even moisture. Do not let the soil dry out, but avoid keep the surface soil constantly wet. In hot weather or dry conditions, lettuce may require watering every day. Keep growing beds weed free; cultivate shallowly to avoid disturbing lettuce roots.

Harvest. Pick lettuce on a cut-and-come-again basis; pick the outside leaves as soon as they are big enough to eat. For heading lettuce–crisphead and Romaine varieties–cut heads as soon as they are solid and firm.

More growing tips at How to Grow Lettuce.

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86 Comments

  1. Live in VA. Planted leaf lettuce a month ago. Sampling of lettuce leaves
    actually BURNS inside of mouth. Did add lime to soil 4 weeks prior to
    planting. Would this have made lettuce toxic?

    • Soil has everything to do with flavor. Yes, the lime may well have left the flavor of your lettuce bitter. Allow a month or more to go by between adding amendments to your growing beds. Watering will allow the amendments and fertilizers to be evenly dispersed throughout the planting bed.

  2. Living in Florida, our winter has been very warm except for a few cold snaps off and on. Our romaine lettuce is already bolting, and we have another light freeze due next week. I harvested all I could yesterday, but it is all tough and some is slightly bitter. I guess it got too hot. We are growing it in a square-foot garden with top notch soil and good drainage. Also, it is not crowded, as I grew one plant in each square foot. Is there any way to use all that tough lettuce?

    • Easily you can add your bitter lettuce to the compost pile, but I assume you might want to try serving it, so try a lettuce stir fry (see below).
      With your next crop of lettuce–when hot weather threatens, place wooden stakes or a wooden frame over the bed and drape the frame with shade cloth to keep the sun and heat from encouraging the lettuce to bolt; also apply cool water.

      Stir Fried Romaine Lettuce
      Ingredients:
      1 head Romaine lettuce
      1 1/2 teaspoons light soy sauce
      1 1/2 teaspoons sesame oil
      1 teaspoon rice wine or dry sherry
      3/4 teaspoon sugar
      1/4 teaspoon freshly ground white pepper
      3 tablespoons vegetable oil
      3 garlic cloves, smashed and peeled
      1/4 teaspoon kosher salt
      Directions:
      Core the lettuce and cut into quarters. Separate into leaves. Wash and dry the lettuce thoroughly.
      Combine the soy sauce, sesame oil, rice wine, sugar and pepper in a small bowl.
      Heat a wok or 14-inch skillet over high heat until hot but not smoking. Add the vegetable oil and garlic, and stir-fry 10 seconds. Add the lettuce and stir-fry 1 minute. Add salt and stir-fry another minute, or until lettuce is just limp. Swirl in the sauce and cook 1 minute longer, or until the lettuce is just tender and is still bright green. Serve immediately.

      Read more: http://www.sfgate.com/food/seasonalcook/article/Cooked-lettuce-becomes-a-hot-topic-2506986.php#ixzz2MJUZhBs0

  3. First time ever! planting lettuce, or have a garden…however, today I went to the garden and found clasters of beluga caviar like substance on the lettuce leaves. What would these things be? please advice.

    • I suspect the dark clusters on your lettuce leaves are cabbage looper or armyworm eggs or the eggs of some other soon-to-be caterpillar. You can crush these eggs between your fingers or wait for the caterpillars to appear and confirm the type of pest coming to eat in your garden (then handpick and destroy the pests). Floral lures or traps can catch the night-flying moths who are laying these eggs.

      • I’m trying to grow lettuce in South Florida but I’m having issues where the plants are leafing out instead of forming a heart .

        Tried seeding in 1/2 inch of soil but it still did not form a heart we are trying to seed it inside with grow lights and a/c to help with the Florida sun because when we try it outside they wither .

        Would you have any suggestions on how to get the lettuce to form a heart

        • Lettuce is a cool-season crop and does not do well when temperatures move into the mid-70sF and warmer; warm temperatures will prevent the formation of heads. In warm-summer regions, plant lettuce during the time of the year when days are shortest–autumn through early spring. Time your planting so that lettuce will come to harvest in the cool time of the year. Grow lettuce where it will receive bright indirect light, not hot summer sun. Be sure to plant in compost-rich, well-drained loamy soil. Space plants as suggested on the seed packet; thin head lettuce to at least 10 inches apart.

  4. I have lost my seed packet for the leaf lettuce (which I believe is what you call the loose leaves that do not grow to a head of lettuce.) My plants now are about 2 inches high and quite close together. Should I thin them? If so, how far apart?

    • Leaf lettuce should be thinned to 8 inches apart if you plan to harvest the whole head at one time. If you are planning to “cut-and-come-again” harvest–which means you will harvest a few leaves at a time, meal-by-meal, then thin your plants to about 6 inches apart.

  5. We did a raised bed this year for our lettuce and used Miracle Grow dirt specifically recommended for raised beds. Planted the seed and it was up within 5 days but now it has grown any since then.
    It’s going on 3 weeks. Temperatures are fluctuating with days in the 60s & 50s and nights 30s to 50s. We have plastic tents we put over them at night and then either take off or vent during the day. Soil doesn’t seem to be too wet or too dry. We also planted onion sets and they’re doing great. Why isn’t the lettuce growing

    • Your night temperatures in the 30s may be slowing the growth of the lettuce. The optimal temperature for leafy crops is 60sF–though lettuce and other leafy crops will grow at slightly lower temperatures. Onions do not mind the cold. If your plants seem healthy, they should begin growing in earnest once temperatures moderate.

    • Mesclun and most leafy crops prefer cool weather. If temperatures move into the 80sF, leafy crops will bolt–send up flowers–and set seed in preparation for reproducing and then death. You can cut off the flowers and stems to slow the bolting process, but the plants will likely be bitter flavored as sugars move from the leaves to flowers and seeds.

    • Lettuce 3 feet tall–the leaves or the stalks with blooms? In warm weather, lettuce–a cool-weather plant–will bolt (send up a shoot and flower) and drop seed; some varieties could get 3 feet tall with flower stalks. If the plant has not bolted and leaves are 3 feet tall, it would seem the soil must be very rich in nitrogen and the plants are very, very happy.

      • If you have ruled out insects feeding on the leaves, warming temperatures may be the problem. Whitish lettuce leaves could be sunburned. Place a frame at the edges of the planting bed and drape shadecloth over the frame to that plants do not get midday sun; early morning and late afternoon sun should be sufficient. Keep the soil just moist; if the weather is warm, sprinkle plants with water in the morning to help keep them cool.

  6. Planted lettuce in a new raised bed. The lettuce started to grow. It is up about an inch and will not get any bigger. It has been 2 months and the weather has been warm in Pennsylvania. Why isn’t it growing anymore? Did I use the wrong soil?

    • You want to use a rich planting mix or native soil mixed with aged compost for lettuce. Keep the soil just moist–not overly wet, and don’t let it completely dry out. Weather too warm may slow lettuce; temps in the 60s to low 70sF would be ideal for lettuce. The plants may take off when the temperatures cool a bit.

    • Your lettuce plant has bolted and eventually will flower and set seed. The leaves will now be bitter–taste a few. You can eat them, but you may simply want to remove the plants and sow again–time your sowing so that the plant comes to maturity when the temperatures are in the 60sF.

  7. Any thoughts on why our baby romaine will only grow 1/4 of its summer time yield in the winter despite having top of the line Lumigrow lighting putting out more than adequate PAR readings. We at first had poorly growing lettuce all around, but then started doing daily air-changes which caused the lettuce to grow much better in regards to color and texture, but still very small relative to the summer yield. We expected about 70-80 percent of summer time yield after adding lights, but have only achieved abround 40-45 percent (same as without the lights). The idea that the lights are doing nothing seems hard to believe. Any suggestions?

    • The less than anticipated growth and yield is likely related to environmental factors: if light is sufficient, next check soil and air temperature; and then water and nutrients.

  8. Lettuce seedlings (Black Simpson and White Paris) from seed in newly estb’d raised beds (full sun) germinate easily but only grow to about 1/2-1″. Same problem with Swiss Chard. Thought it might be warm weather, but cooler temps have not helped. Beds contain garden soil amended with composted rabbit berries. Gladly welcome your thoughts/suggestions. Location: Austin, TX.

    • Rabbit manure is high in nitrogen. While leafy crops generally like nitrogen, too much nitrogen early in growth can stunt leafy crops.
      Re-plant in a bed lower in nitrogen to see if that is the cause. Generally, poor seedling growth is often related to environmental factors (such as soil nutrients), other factors would include too much or too little soil moisture, day or nighttime temperatures too warm or too cool, and too little or too little sunlight.

      • Ok. I don’t think I added an over abundance of bunny berries. I’m still puzzled since the cool temps and watering have not been a problem. My guess is that the dirt in these new beds is nutrient deficient. Might try planting a few peas as a test. They’re currently growing vigorously in some of our older beds. Thanks for your help.

  9. Help! My lettuce is being eaten by the leaves and there are huge holes when I check in the morning. I don’t know what type the bugs are, but there seem to be black little eggs underneath. Please advice.

    • There are several insects that lay black eggs on the undersides of leaves–beetles and caterpillars are two. Crush the eggs with your fingers–use gloves if you are squeamish. Check the undersides of leaves to see if you can find the insect; crush the insect as well. You can spray the leaves with insecticidal soap–but that is a contact poison and usually will not kill the pest it does not touch. You can sprinkle diatomaceous earth around each plant–that is a silica that will injure and kill most crawling pests.

  10. hi,
    I live in Iran,Tehran..
    I planted the lettuce in the pot in our home and the seed is germinate but after 2 weeks, this but do not grow and wither ..
    I dont know how can I do….!!!?
    please help me..
    also the soil is very good.

    • There are several possible reasons for the failure of young lettuce plants; here are a few (1) temperatures too warm or too cold–be sure to plant lettuce in the cool, not hot time of the year; also protect plants from frost in winter; (2) the soil is too wet or too dry–keep the soil just moist; (3) too much nitrogen in the soil–for plants growing in pots use a commercial potting mix, not a planting mix; you should not need fertilizer; if you do use a fertilizer, only use half the recommended strength. You may want to start the lettuce seed indoors and transplant it out to the container when it is 3 to 4 inches tall.

  11. Hi. What does it mean when lettuce (about 3 weeks old) is slightly yellow but nearby plants all look great? The lettuce plants are unblemished and otherwise look perfect, but the entire leaves are evenly pale, a slight yellowish green? I used miracle gro soil so they have not been fertiized yet except for a little bit of worm casting.

    • Yellowing lettuce leaves on young plants: there are a few possible reasons: (1) the soil is too wet or too dry; try to keep the soil evenly moist; the moisture holding capacity of soil can differ from spot to spot in the garden; (2) too much nitrogen can cause leaves to yellow, but if only a few plants are yellowing, give them a dilute (half dose or less) of fish emulsion–this may give them a boost; (3) avoid feeding with worm casting early in the plant’s life; worm castings are very rich in nitrogen; too much nitrogen can cause leaves to yellow.

  12. Very very good information I really enjoy reading all the questions and answers –by way Steve I live on the tropics in Central America around 400 meters over sea level what kind of vegetables can I grow in a greenhouse normal temperature year around 92f Rein or shine —also I did orden some romaine lettuce for hot weather all I am doing is a small experiment in a little 4000 sad greenhouse to see what’s work and what not i have try to buy all my seeds for hot weather I am installing some kind of screen so the air can flow and many many fans and exhaust—and finally does lettuce hate heat or direct sun shine???? If I cover the lettuce inside the greenhouse with a shade still the heat inside will affect it —

  13. This is my first year gardening. My lettuce plants were doing amazing until a groundhog found his way in and wreaked havoc. Can or should I salvage the plants. He nibble most but not all of the leaves.

    • Lettuce is fairly quick to germinate and grow so you can start another crop to grow on next to the one that was damaged. The damaged plants my sprout new leaves if the crowns were not damaged. Cover the crop with a floating row cover to keep pests from eating the leaves.

  14. I am growing green leaf lettuce indoors under lights in northern Michigan. Soil is composted leaves and composted horse manure with generous vermiculite. Lettuce germinates and grows quickly producing great leaves for cut and come again. Recently, leaves have developed small bubble like raised patches between leaf veins. Almost like something is sucking the juices out of the cells between the veins. There is no evidence of bug or eggs. Wish I could send you a picture. Any thoughts on what this could be? At first I thought nematodes, but nematodicide has had no effect. Thanks for your thoughts.

    • Sap sucking insects can cause leaf tissue to look puckered or blistered. Mix a few teaspoons of liquid dish soap with one quart of water, then spray or wipe the solution onto the lettuce leaves and stems. If insects such as spider mites, thrips, or aphids are present this should dispatch them. If the problems persist the likely cause would be a fungal or viral disease. Bottom rot fungal disease is marked by rum-colored sunken lesions which commonly started near the base of leaves where there may be contact with the soil. Well-drained soil can help prevent many fungal diseases. Big vein virus disease will cause yellow along the veins; leaves will thicken and become brittle. The soil must be replaced. Bacterial diseases will cause leaves to rot; bacterium also live in the soil and are often spread by splashing water. Avoid wetting the leaves and rotate the crop or change the soil.

  15. Hi.
    Growing igloo lettuce from seeds. Started out strong the stems grew very tall in a few days and now they are all lying on their sides in the pot the stems themselves are like 2 inches long and don’t seem strong enough to hold themselves up is.this normal?

    • Igloo head lettuce will be leafy to start–before it forms a head. Early on keep the soil just moist, not soggy and never dry. Make sure the pots are large enough to support rapid root growth. The ideal temperature for lettuce growing is the mid 60sF with plenty of sunlight. If the leaves are laying on the soil cover the soil with a poly plant blanket to keep the leaves from rotting until they gain strength.

  16. I am regrowing my romain lettuce. I just transferred yo soil after seeing leafs regrow. After a couple hours the leafs became soggy. Any recommendation on regrowing romain lettuce?

    • Soggy lettuce leaves almost always means the soil is too wet. You want the soil to be just moist, not wet. Take up a handful of soil and make a fist; if the soil is a wet ball when you open your hand, it is too wet. If the soil lightly crumbs when you open your hand, it is evenly moist. To regrow lettuce, be sure the roots are wet covered but the crown of the plant is not buried.

  17. I have small dry brown spots on my leaves. Otherwise the lettuce looks healthy and happy. Is the lettuce still safe to eat or is it diseased?

    • Dry spots on lettuce leaves can simply be sunburn. However, if you have sprayed in the garden with chemicals, chemicals also can cause a burn. If the leaves are simply sunburned you can eat them.

  18. I’m growing red leaf lettuce, and a few of the leaves turned brown and are kind of crunchy. They crumble a bit when I touch them. I’m assuming this is from sunburn (I live in CO, and we have 70-degree weather each day), but I’m not sure how to fix it. Suggestions?

    • To avoid lettuce leaf sunburn, place a piece of shade cloth directly over the plants. This will protect the plants from midday sun but allow them to still get morning and late afternoon sun.

  19. Growing a mesclun blend from seed. I used potting soil to germinate. They seemed happy. I transplanted into my garden. Now the leaves seem limp. I live in Massachusetts. The weather is perfect for lettuce. I think I might be over watering. Any suggestions?

    • It’s not unusual for transplants to suffer some shock in the days after transplanting. Keep the soil just moist with a light spray in the mornings. If nights fall below 60F cover the plants until they are more deeply roots and gain strength.

  20. Thankyou for excellent advice growing lettuce. I have planted mid autumn crops of spinach and lettuce in new raised beds near Sydney. Seedlings came up, then nothing for two months. Think I’ve found my soil problem.

  21. I planted mesclun mix in my garden, the green leafy variety came up quick, and now the purple variety and spinach is coming up but some of the green lettuce plants have little spines all over them. Are they diseased? Should I pull them?

    • Check the label of your seed mix to see what greens are included in the mix; some green have leaves that are deeply cut, some greens have edges or folds that may appear spiny. Research the greens included in your seed mix; you will find pictures on the internet. These may have been included in the mix. That said if some of the leaves do not look palatable, don’t eat them.

    • By side shoots do you mean stalks; if so, the plant is flowering; flowering is triggered by warm weather. If by side shoots you mean, small plants nearby, it could be that the planting bed was amply seeded and new plants have germinated and begun to grow.

  22. First time growing any veg. I planted out iceburg lettuce into raised planters that i had growing in my greenhouse but within a week the underside of the leaves started to get a red tinge to them and they look as if they are wilting, i do give them an occassional feed with seaweed extract. Why would this be happening?

    • The red tinge is likely a fungal or bacterial disease. Do not overwater the plants. If the soil was not new when you planted, you will want to replace the soil before planting again. You can place a horticultural cloth around the base of the plants to keep the leaves separated from the soil. If temperatures average greater than 85F, pull the crops and replant in the cool time of the year.

  23. Hello Steve. We are growing varieties of lettuce very successfully however the romaine is not as lush Or growing as large and the leaf edges are brown and dry looking. We are having a cool wet season so far. I have planted new plants in a different location to test but would appreciate your thoughts.

    • Leaf edges can brown when the soil stays wet. If wet weather is regular where you are, plant lettuce on mounded rows to ensure full drainage. Conversely, if lettuce goes dry leave edges will also dry and brown; this can happen if soil moisture is inconsistent–dry, then wet, then dry.

  24. My iceberg lettuce is about a foot-and-a-half tall, I’ve just recently spread them out and I’m going to have to be very careful since they’re starting to wilt( I think I may have damaged The Roots) . What do I do about the tall lettuce.

  25. My leaf lettuce has been growing great in a container on a second level deck. However the leaves are turning very pale. Uniformly thru all the lettuce. Is it too crowded for the container and not enough nutrients or perhaps too much sun? We are in Michigan.

  26. Hi, I planted already grown lettuce about 2 weeks ago that I bought from a shop that happened to still have roots, it was planted in a small plastic pot and dish and has been kept indoors on my South facing windowsill. It was an immediate success and looked healthy and happy over week 1.
    I noticed its a thirsty plant and seemed dry every morning (whereas my rosemary, which was drinking loads of water in the summer, has now needed watering about every three days or else the soil stays damp. just for comparison), I noticed this also during the day because it seemed to very quickly start to ‘droop’ and look ‘sad’ but perked up as soon as I gave it water.

    Cut to this week and the soil is seeming to stay damp, yet the lettuce plant only droops in the day and in the morning is looking very perky and edible, by the end of the day the leaves are very bitter and look almost like wilting. This morning I left it alone as it looked very happy compared to yesterday, looked at it just now and the outer leaves are starting to droop and the green doesn’t look as shiny, it only sat on the windowsill.

    I live in UK, Slough. It’s been grey and wet weather for about 2 weeks with the occasional sunny spell. This morning was sunny and about midday it became overcast an grey (I’ve had to switch on my lights).

    Any help as to why it is possibly drooping and how to remedy it would be much appreciated. It a leaf lettuce by the way, not sure on variety but its got red and slightly jagged edges, but a green center.

    • It will take a bit of detective work to determine why the lettuce is perky in the morning and drooping during the day: (1) is the daytime temperature in the house warmer than the nighttime temperature; the lettuce may be reacting to temperature; (2) leafy crops can wilt when underwatered and overwatered–be sure the soil is staying just moist; you can use a soil moisture meter to determine what the moisture is when the plant is perky and what the soil moisture is when the lettuce is drooping; (3) indoor growing plants need 12 to 14 hours of bright light each day; you may want to place a grow light over the plant.

  27. I’m trying to grow lettuce inside. Seems as though my advice I was given was so different than yours, and seeds are growing long sprouts with one leaf on top. They wilt, and die.

    I was told to plant 1 inch apart, and they sold me a heat mat to keep the soil warm. It seems all of this is wrong and probably why it’s not working.

    From this, I think it seems I need one seed per pot, no heat mat, and I have grow lights that don’t give off heat that I’m using for 12 hours. maybe too much sun?

    • OH I see you actually recommend 12-14 hours of grow light light per day. Perfect! I am also using Happy Frog, which someone said it has too much nutritient content. SO I switched one pot to regular potting soil

    • Use the heat mat until seeds germinate. Place the seedlings a few inches below a grow light or fluorescent light for 12 to 14 hours per day. When seedling are a few inches high introduce light air circulation with a fan to help the seedlings gain stamina and grow stout.

  28. Hello, I planted out young seedlings. (They’re only about 1 1/2” tall) Now we’re getting a heavy rain. Should I cover them with jars or jugs? I’m worried they’ll wash away or get quite “flattened” by the rain.

    • Yes, protect the small seedlings with milk jugs with the bottoms cut out–or place a frame or stakes at the corners of the bed and drape clear plastic or horticultural cloth over the frame; remove the coves on clear days.

  29. I planted spinach and lettuce recently and it came up beautifully. But, now some of the seedlings are dying and when I pull them up they have no roots. What is going on?

    • This is likely caused by damping-off a fungal disease that can live in the soil and is transmitted into plants through water uptake. Make sure the soil is well-drained and if you are growing in containers use new potting soil. Start the plants in sterile potting mix indoors and keep them growing in pots until they are 3 or 4 inches tall–then set them in the garden.

  30. My lettuce heads have developed a brown/dark greenslime throughout the heads (especially bad toward the outside). A mushroom based soil enrichment was worked into the soil before the planting. What could be causing this?.

    • If the mushroom-based soil was tainted with a fungal or bacterial disease, those diseases would, in turn, infect your crop. What you describe is likely a fungal or bacterial rot. Bottom rot started on the lower leaves and spreads until the entire plant is rotted. Remove infected plants. Replant in another location.

  31. Some of the iceberg lettuce I’m Growing has turned pink. I’m new at growing vegetables this year. Is it ruined? I’m in zone 8a. The weather fluctuates 60’s – high 30’s at night.

    • There are a couple of reasons lettuce leaves turn pink: (1) the lettuce has grown well past its harvestable, maturity; (2) a fungal disease has invaded the leaves. It would be best to remove the plants that are pink and not eat them. You can start new plants–this time of year leaf lettuce is a better choice, but you will likely need to use row covers to protect them from the nights in the 30s. Leaf lettuce can be harvested a few leaves at a time; this will allow for continuous harvest.

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