Growing lettuce is easy

To avoid bolting, lettuce needs to be grown quickly, without any check in growth, but this also causes problems in hot weather. Tight heads of fast growing lettuce generate a lot of heat from their own metabolism and in hot weather they can literally cook from the inside. for these reasons, growing lettuce is generally kept to early Spring.

Germinating lettuce seed can also be a bit tricky as it requires more soil moisture than most other vegetables and it has its own peculiar dormancy mechanisms. This means that soil temperatures that are too low or too high will prevent germination, but lettuce seed is also sensitive to infra-red light. This tells the seed how deep it is in the soil - too deep or too shallow and again the seed will not germinate.

This makes planting lettuce as seedlings a more practical option than trying to germinate the seed yourself. However, even here there can be trouble.

Lettuce has a fairly poor root system, so successfully growing lettuce requires doing everything you can to maximize root growth. So when shopping for lettuce seedlings, choose smaller ones that show no sign of roots growing our of the drainage holes in the punnet or seedling tray. these will be easier to separate without causing root damage and will have the best chance of developing stronger root systems after transplanting. Another good idea is to water the newly transplanted seedling in with a weak seaweed extract solution, as these contain plant hormones that will stimulate root growth.

Soil and Fertilizer

Because of the need to stimulate strong root growth, soil preparation is very important. If you have not been there yet, you should read the information in our soil improvement section. Don't make the mistake of thinking that all you need to do is pile on lots of fertilizer and organic matter, there is much more to it than this.

Lettuce is a gross-feeder, so fertilizer is important. This means that growing lettuce is always done in the first stage of your crop rotation.

Of course, it is not just the amount of fertilizer, but the type. For organic production, poultry manure and mushroom compost work best and regular application (every other week or so) of a weak seaweed extract solution will help ensure you don't run short of trace elements.

The best way to provide good, balanced plant nutrition when growing lettuce is to work out your fertilizer requirements directly from the results of a good soil test. No, not a cheap soil testing kit that you can get off eBay! These are not nearly reliable enough and do not give you the detailed information needed to properly work out a program for balanced plant nutrition.

Pests, Weeds and Diseases

The most common pests encountered when growing lettuce are slugs and snails. Those involved with Permaculture will tell you that snails are a sign you have a duck-deficiency. However, with ducks you may also have a sudden lettuce-deficiency!

Of course, I do not recommend chemicals or snail bait. Snail bait often kills more pet dogs than snails and here in Australia, it also kills our native Blue-tongue lizards (from eating poisoned snails). so let's try some other options.

Perhaps the best control is a combination of straw mulching and beer traps. Snails do not like crawling over straw. In fact, this is so effective, it is how strawberries got their name!

Beer traps are simply small plastic containers buried up to their brims in the soil. A small amount of beer in the bottom will lure snails in to their doom! They are not a quick fix, so set them up early and keep them going as a means of keeping the snail population down.

Diseases like mildew are most often the result of planting too close or in the wrong situation so that air movement &/or sunlight are restricted and the plants are under stress. Otherwise, your regular seaweed applications will serve to prevent most things.

Here is a very good reference covering various disease problems in growing lettuce (together with some handy nutritional data).

Weeds can be a problem because some are actually wild species of Lettuce, but see our Weed Management page for more information on dealing with these problems.

Types of Lettuce

When growing lettuce, your are cultivating a domesticated variety of a common group of thistle-like garden weeds. In fact, lettuce belongs to the daisy family so even plants like dandelion are quite closely related. Many of the Wild lettuces (like the American Blue Lettuce) are known to have been used as food or medicine since antiquity. The Ancient Egyptians even used the milky sap of wild lettuce as a medicine known today as Lactucarium.

The various groups of cultivated lettuce and related plants include:

• Romaine or Cos Lettuce
  With tall, loose heads and fairly stiff leaves that can become coarse, and bitter if not grown well. Practice your growing methods on other varieties before trying cos lettuce.
• Crisphead lettuce
  The common 'iceberg' style lettuce used in most salads.
• Butterhead lettuce
  Small lettuces with soft hearts and smooth glossy leaves. The wide range of varieties with varying shapes and colors makes this group very useful. It includes varieties like Tom Thumb and Mignonette.



• Loose-leaf or bunching lettuce
  This is the group used in salad mixes, including Oak-leaf lettuce, this group also has a range of colours and leaf shapes.
• Celery or stem lettuce
  Also called Chinese lettuce, Celtuce or Asparagus lettuce, this is less commonly grown. It looks like a Cos lettuce, but individual leaves are harvested as the plant continues growing up a long stem and the stem itself can also be cooked and eaten.



• Chicory, Endive, Witlof and Radiccio
  Not actually lettuce at all, but sometimes used as lettuce alternatives and grown in similar conditions, but with more heat tolerance. These will be discussed in detail on their own page.

Clearly, growing lettuces is a very big topic, so rather than try and put everything here, there are some useful links below. However, we will be adding more information from time to time, so why not keep in touch by subscribing to our Free email newsletter - The Food Gardener.

Further Reading and Useful Links

Nutrition facts about lettuce
This is about the most detailed nutritional information you could possibly ask for.