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Top Problems Growing Lettuce and How to Fix Them

Lettuce can be one of the easiest plants to grow at home because of the short amount of time it takes to sprout and the amount of it which can be put in the ground. However, many people struggle to get their plants to grow or experience changes in color or texture once they are mature. To solve these issues, you will need some advice.

The top problems growing lettuce are halted growth, plant death, changes in color, dark spots or stains, leggy-ness, bolting, and lack of head production. These issues can be countered using techniques such as increased watering, relocation, chemical aides, thinning, and strategized sowing.

All of these issues can prevent you from harvesting healthful and nutritious lettuce. When planning your garden, you want to see the best results possible come harvest season – read on for more information on how to get there.

Your Lettuce Plant Has Stopped Growing or Is Dying

Sometimes when we plant vegetables or herbs, the seeds or seedlings won’t take root, and the growth of our plants will halt. Even worse, your plants might even start to show signs of death. Since lettuce is such a fragile plant, it’s important to keep an eye out for any signs of stunted growth or death. A watchful eye on your plants will help you avoid some of the major drawbacks of cultivation and will teach you how to respond to the needs of your crops more effectively.

Lettuce is prone to wilting and therefore needs to be watched closely. When your lettuce plants stop growing, this likely means that it lacks the major plant needs – nutritious soil, sunlight, and water.

To be able to grow properly, the soil in which you’ve planted your lettuce needs to be well-balanced with necessary nutrients like nitrogen, potassium, and boron. To determine the quality of your soil, you’ll need to take a soil quality test. Soil quality tests are easy to use and can be obtained at many hardware or farm supply stores.

If soil deficiencies arise, you’ll then need to supplement with a specific fertilizer or bone meal. You don’t need to fertilize with every watering – simply add a little fertilizer to the top of your pre-existing soil every couple weeks/month or according to the package instructions. Locally made compost is a great option to add to your plants. Check in with a local farmer or nearby farm supply store to see if they have any compost for sale.

Lettuce plants also need a fair amount of sunlight – not so much that they will be scorched but not too little that they don’t grow. Make sure that you are planting them in an area that has moderate lighting so that they will grow effectively. You should also make sure that your plants have enough warmth; it is very difficult for lettuce plants to survive freezes, so ensure that your lettuce is planted after the last frost.

Lettuce plants have a very hard time coping through frost and freeze. They are some of the first vegetables to die off when an unseasonable frost arises. When lettuce is left out to freeze, they will likely start wilting once the weather warms back up. The growth of the plant will be stunted, and depending on the amount of time they spent below freezing, they may die off completely.

Finally, lettuce needs to be watered frequently and shouldn’t be allowed to dry out. Since lettuce is mostly water, this means that the plant requires more hydration than many other varieties of vegetables and herbs in your garden. Keep an eye out for dry soil.

Your Lettuce Plants Are Turning Pink or Red

If you regularly eat iceberg or romaine varieties of lettuce, you have likely seen lettuce that is colored with rusty pink/red streaks or stains. You may wonder whether or not this lettuce has gone bad, but there is no need to worry – this simply means the lettuce is getting old.

Though this problem usually occurs after harvesting, it’s possible that your lettuce plants may start to become a rusty color when they are still growing. Unfortunately, there is no way to reverse this issue. This means that you will have to harvest the heads of lettuce immediately to avoid the issue worsening.

However, pinkening lettuce is perfectly fine to eat. This pinkening is caused by oxidation. The process of oxidation is what happens when vulnerable compounds in foods are exposed to oxygen, causing a chemical reaction that changes the color of the vegetable. Other foods that face oxidation are apples, bananas, potatoes, and pears.

Your Lettuce Is Leggy

Leggy-ness is an issue that presents itself early in the growing stage of planting vegetables like lettuce. It is important to note that leggy-ness has different causes depending on where the seeds were started (indoors or outdoors).

If your seedlings were started indoors, it is likely that your plants are leggy because they haven’t had enough exposure to light. When young plants do not have enough exposure to light, they tend to stretch and reach upward in an effort to get closer to the sun. This means that they will have long, thin stems with very few leaves because growing thick stems and leaves take up too much energy.

If you have started your plants indoors and they have become leggy, an easy way to give them more sun is to move them to a new spot in your home. Make sure you can find a place by a window that gets at least 6-8 hours of bright sun daily.

Another alternative is to use a grow light. Grow lights are helpful because they allow you to target your seedlings with an exact amount of light. Many grow lights, such as the GHodec Tri-Head Plant Light, have timers that you can set, which keep the light on for four, eight, or sixteen-hour intervals.

If you’re growing your lettuce outdoors and you are still experiencing leggy-ness even though you’re sure the plants are getting enough sunlight, then you are probably exposing them to too much heat. To remedy this issue, always consider relocating them to an area in your garden with more shade and make sure to keep the soil around the plants damp to combat the heat.

Your Lettuce Plant Is Turning Black or Brown With Spots

When your lettuce plants start to show signs of spotting, it’s time to take a close look at what might be going wrong in your garden. First off, you need to take a peek at the details of the spots on your plant. What color are the spots? Usually, spots on lettuce plants appear in either a light brown or black color.

Next, you’ll need to take a look at the texture of the spots on your lettuce plants. What do they feel like – are they soft and moist, or are they dry and flaky? These are all important characteristics to take into account when researching ways to solve your lettuce troubles.

If your lettuce starts turning brown, you are likely dealing with a case of bacterial leaf spot. Bacterial leaf spot is caused by bacteria in the soil that, through watering, planting, and normal, natural garden occurrences, has penetrated the lettuce plant and is rotting it away.

Unfortunately, there is no way to cure bacterial leaf spot. You will have to isolate and prune the lettuce plants that are already infected with leaf spot. Make sure you take care when watering and picking lettuce as not to spread the infection to other plants.

Another reason you should pay attention to the color and texture is that bacterial leaf spot can also manifest itself as small black spots on lettuce leaves. Eventually, leaf spot can also take over the whole plant, not just as a series of mushy brown spots but entirely turning the plant dark black. The earlier you catch leaf spot, the better. This will help you maintain more harvestable lettuce and keep it from spreading too quickly.

Your Lettuce Is Turning Yellow

Lettuce is a helpful addition to most people’s gardens because it is easy to grow and, depending on the variety, can yield a large amount of food for you and your family. Lettuces can be anywhere from a bright green color to deep purple and are filled with nutrients. However, lettuce plants can also become prone to yellowing if not taken care of properly.

When lettuce plants turn yellow and soft, the most likely case scenario is that they have a case of Fusarium wilt. Fusarium wilt is an infection caused by the Fusarium fungus. This can be a difficult affliction to deal with in your garden because it has the potential to completely kill your lettuce plants.

There are a few different ways to combat Fusarium wilt. The first way to rid yourself of this fungus is to simply pick and dispose of the affected plants. By doing so, you are preventing the disease from spreading from the affected plants to other ones that aren’t yet showing symptoms.

The issue with fungal infections on plants is that they often don’t just spread through other plants but also through the soil they are planted in. Fungus can live in the soil without plants to feed off, so it’s important to note where in your garden the fungal infections happen so they can be prevented in the future.

If removing the affected plants doesn’t solve the issue of Fusarium wilt, you will need to utilize a vegetable-safe fungicide in your garden. A helpful option that you can use on your vegetables is the Serenade Garden Organic Fungicide, which is safe enough to use on your edible crops.

If even after using a vegetable-safe fungicide, you are still dealing with issues of Fusarium wilt, you may have to scrap your lettuce crops altogether and call it a loss for the season. Take this time to plan your garden for next year. Make sure to select a variety of lettuce that is wilt-resistant, such as the Duquesne romaine variety. 

Your Lettuce Plants Are Bolting

Lettuce plants are not normally thought of as plants that flower. However, lettuce can actually let off blooms with tall stems if they are not kept under the correct conditions. If you find yourself with a crop of lettuce that’s producing flowers, you have a problem on your hands.

When lettuce plants bolt, that is a telltale sign that your plants are under too much heat stress. Heat stress is caused by temperatures that are consistently too high, or it is caused by a sudden spike in temperature. These hot temperatures cause the plant to grow a flower.

Another problem with bolting is that the process of bolting has the potential to turn lettuce bitter. To prevent this from happening, you will need to make sure that your plants don’t get too hot. If your lettuce gets too hot, it will be quickly ruined.

If you anticipate a hot growing season, make sure to plant your seeds or seedlings in an area with moderate shade and also make sure to water them consistently. This will help mitigate some of the negative effects of heat on your plants.

If you anticipate a cold snap, you can (very gently) lay a cloth or blanket over your lettuce plants to trap in some of the heat that is held in the soil beneath the plants. This way, when the temperatures go back up the next day, then your lettuce plants won’t be in such a state of shock. 

Your Lettuce Plants Aren’t Forming Heads

If you are relying on your lettuce crop as a source of food for you and your family, it is important that your plants are given the resources they need to form heads. These heads are the main portion of the plant that give us the ingredients for our salads and sandwiches.

When your lettuce plants aren’t forming heads, it may be because you haven’t organized your garden properly. Lettuce plants need a lot of space to grow. When you first plant your seeds or transplant your seedlings, make sure to thin them out, so each plant has enough room to spread out. Most gardeners suggest anywhere from eight to twelve inches of space between them.

If you are already dealing with full-grown plants that haven’t produced a head, consider thinning them out to give some of them a chance to thrive. This way, the ones that are left after the thinning can take more energy and nutrients from the soil and absorb more water, letting them form solid heads.

Another reason your lettuce plants may not be producing heads is that they have been planted at the wrong time. According to agriculturalist Bonnie L. Grant from Gardening Know How, lettuce plants shouldn’t be exposed to too much warm weather when they are growing.

Copyright protected content owner: and was initially posted on June 13, 2020.

She suggests that people plant their lettuce seeds or seedlings either in the early spring to avoid the hottest days of the summer, or at the end of the summer so that they can be harvested in the fall. Either way, the middle of summer in four-season climates is no good for growing substantial lettuce plants. 

Your Lettuce Plants Are Turning Purple

Lettuce works well in most vegetable gardens because of its ubiquity – everyone has tasted lettuce and knows how common its addition to meals is. Most people are familiar with green varieties of lettuce, but fewer people are accustomed to consuming purple lettuce.

Sometimes lettuce turning purple isn’t an issue at all. If your lettuce plants start to turn purple, make sure that you didn’t unknowingly plant purple or multicolored lettuce. Some purple varieties are completely violet colored with a rich eggplant hue, while others are simply tinted on the tips of the leaves with soft violet.

If you’re sure that you didn’t plant purple lettuce, then you may simply be dealing with a case of oxidation. Just like when lettuce turns pink, red, or rust-colored, lettuce may also begin to take on a purple hue.

Final Thoughts

Lettuce is one of the most commonly grown vegetables in the country, with hundreds of varieties available for purchase in grocery stores, mega-marts, and farm supply shops. Lettuce is a relatively easy vegetable to cultivate at home, but it does take some technique to be able to manage the issues that arise with the plant.

Copyright article owner is for this article. This post was first published on June 13, 2020.

Sometimes your lettuce plants will turn unusual colors like red, pink, or purple. These colors are relatively normal and are simply a result of aging. Other times your plants will turn brown or black, which indicates they are being attacked by fungus or bacteria and need to be treated.

If you are experiencing issues with growth or flowering, know that these issues can be as easy to solve as rearranging, watering, or fertilizing your crops. Enjoy these helpful tips for growing lettuce and happy harvesting.

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