Think Like Lettuce to Extend Salad Days
Chris Smith, the community coordinator for Sow True Seed—an Asheville-based company that specializes in open-pollinated, heirloom, and organic seeds—answers common gardening questions in this regular column for Smoky Mountain Living.
I want to grow lettuce into the summer. is there a way to stop it bolting so quickly?
It does seem somewhat unfair that just as our beautiful ripe salad tomatoes start producing, our lettuce crop begins to bolt and the leaves turn bitter. Bolting is when the lettuce sends up a flower stalk. The hot weather makes the lettuce think it’s days are numbered and the urgency to flower and set seed kicks in. While lettuce will always be much happier in cooler weather, it is possible to grow it through the summer with a few tips and tricks. First, you’ll need to think like the lettuce and attend to its needs. Second, you can plant varieties that are slow to bolt and less bitter in the heat. Third, you can plan small successive plantings of lettuce in anticipation of it’s shorter life cycle.
Thinking Like Lettuce The urge of lettuce to bolt and produce seed is increased when the lettuce feels stressed. During our summers that stress comes in the form of heat and thirst. Most of our fruiting vegetables need full sun to be really productive, but with lettuce we are eating the leaves and it doesn’t require full sun to grow. A couple of my vegetable beds get summer shade in the afternoon from a large tree and this is where I’ll always plant my summer lettuce. If you don’t have natural shade then your local garden center will likely sell shade cloth, which can achieve the same stress-reducing protection. In summer the water needs are higher, so it’s important to make sure that the plants receive a good deep soaking during dry weather.
Heat Tolerant Varieties Sow True Seed conducted a heat tolerant lettuce trial last year. The aim was to look at how quickly certain lettuce varieties bolted and how well the lettuce varieties tasted as they began to bolt. It was interesting that some varieties still tasted pretty good as they began bolting, but other varieties tasted bitter before they got anywhere close to bolting. Here are our top three lettuce varieties which maintained good taste and were slow to bolt. Give them a go this year.
- Chrystal (a batavian lettuce)
- Black Seeded Simpson (a loose leaf lettuce)
- Parris Island (a romaine lettuce)
Succession Planting I’ve spoken about succession planting before and it really is a great tool in the home garden. Instead of planting a whole bed of lettuce which will give you an overwhelming amount of salad for a short period of time and then bolt, you should plant in small successions. Every 10 days or so plant a new row of lettuce. If you are working with traditional 8x4 beds, sow 4-foot rows instead of 8-foot rows. This will mean you’ll always have some lettuce in a good state of edibility. As older lettuce bolts with the heat, newer lettuce comes into production. You can apply this with many crops, but one important note with lettuce is that the seeds will not germinate in high soil temperatures. I would suggest that you sow lettuce seeds indoors in flats once you get into July and August. You can keep the 10 day planting schedule, but you’ll have the extra step of transplanting your lettuce outdoors once its a couple of weeks old.
What summer vegetables can I grow in containers?
I’m a big fan of container gardening. With more people growing food in urban centers, I love it when I see all the creative container gardening that’s going on out there. The really short answer is that you can grow almost anything in a container but you’ll have to pay much closer attention to water and nutrient needs. The smaller the container you use the more attention you’ll have to pay, and if the container is too small then it’ll affect the growth and yield of whatever you are growing. A good tip is to look at the mature spacing number listed on your seed packet and use that as a gauge for the size of container that type of plant will need. Last year the Ag Director at Sow True Seed grew an entire vegetable garden in five-gallon buckets.
Her biggest challenges:
- The cost of good quality soil to fill all the buckets was high.
- Wind toppled the taller heavier plants.
- Keeping the plants well watered through the hot summer was time consuming.
Her biggest successes:
- The buckets could be moved to the places with the best sun—a mobile garden!
- She got creative with shared trellising and stacked buckets.
- It was really quick and easy to add more ‘garden’.
Common container grown summer vegetables include determinate or dwarf varieties of tomatoes (they have a more compact growth habit), bush beans, greens, cucumbers (pickling cucumbers tend to be bushier), basil and flowers. Sow True Seed sells an Urban Container Garden collection to get you started and offer some inspiration!
Find more information at sowtrueseed.com