Lettuce Trial Results May Help Choose Best Lettuce to Plant

In 2020, Master Gardener Ken Elkin set up a lettuce demonstration trial garden, to compare the productivity of various lettuce varieties throughout the summer. There were 3 plantings in the season, with details and results below.

First Round - April to June

4/5: Lettuce seeds in multiple varieties were sown under lights at home.

4/12-22: Seedlings were potted in 4-packs, continuing under lights.

4/25-5/1: Flats of 4-packs moved to my unheated greenhouse.

5/15: Four varieties were planted in the MG beds 5 and 9, in this initial round.

6/8 and 6/10: 26 plants were harvested, averaging ½ lb. each.

6/13: 17 more plants were harvested, and the plot cleared

Catalogue descriptions of the varieties:

Buttercrunch: Compact heads with luscious buttery taste. Mid-green, thick, juicy, crisp, sweet leaves with unique Bibb flavor. Sow either spring or fall. Slow to bolt.

Little Gem: A miniature green Romaine with a blanched, delicate flavored thick heart that remains a single-serving treat! Heads measure 4 inches across and are best harvested from 4 -6 inches tall

Red Salad Bowl: Slow to bolt, with pretty rosetttes of wavy, rounded, crisp, sweet leaves. No heads.

Green Ice: Crisp, glossy savoyed leaves withstand heat are slow to bolt. Tight, compact heads 9 inches across have an unusual, delicate flavor.

Results of first round:

All of them performed well in this first round. 33 linear feet of row produced about 21 pounds of lettuce. Red Salad Bowl was a little spindly to start but developed nice contrasting color for a mixture of greens. Buttercrunch seems to have the most pleasing flavor. Green Ice developed the largest plants. Little Gem was larger than the description, but still quite usable.

Second Round of the trial - June to July 2020

5/31/20: seeds of two varieties were sown under lights at home

6/6/20: seedlings were moved to 4-packs

6/10/20: seedlings were moved to greenhouse

6/13/20: Buttercrunch seedlings planted in Bed 9 and Nevada in Bed 5 the garden.

7/20: Plants were harvested several times

8/8/20: Final plants harvested and the plot cleared

Catalogue description of the varieties:

Buttercrunch: Compact heads with luscious buttery taste. Mid-green, thick, juicy, crisp, sweet leaves with unique Bibb flavor. Sow either spring or fall. Slow to bolt.

Nevada: This extremely uniform, all-green Batavia type lettuce performs in all kinds of climates. Nevada has a tall open head with thick, bright lime green leaves that are crunchy and have a wonderful nutty flavor. Very resistant to tip burn and bolting.

Third Round of the Trial - August to October 2020

08/05/20: Seeds planted under lights at home

08/10/20: Seedlings potted under lights

08/16/20: Potted seedlings moved to shaded greenhouse

08/30/20: Seedlings planted in bed 5 at Master Garden.

10/10/20: Nearly ready for harvest; plants moved to row-covered bed at home for a few more days of growth

Catalogue description of varieties:

Buttercrunch: Compact heads with luscious buttery taste. Mid-green, thick, juicy, crisp, sweet leaves with unique Bibb flavor. Sow either spring or fall. Slow to bolt.

Winter Density: is an early, compact romaine. Its dark green leaves with an upright growth habit build an 8 inch tall densely packed head. Delectable, and it holds well at the market also. Quite bolt resistant and suited to all sowing dates.

Results of third round

Lettuce appreciates the cooler temperatures, but of course it is slower to mature in the declining daylight of fall. Few of the Winter Density seedlings survived. I moved all of the plants home where I can manage row-covering daily when frost and deer threaten. Excellent flavor in this late crop.

Summary Comments

Following the success of last year's string bean trial it was decided to work this year with lettuce. The beds in the Master Garden were amended with mushroom soil, compost, and organic fertilizer. Spring growth of lettuce is the easiest to manage, and has the largest harvest by far. Mid-summer is tricky because of the needed attention to shade and regularity of watering due to heat and drought. Seedlings for the fall season seem to appreciate indoor sowing and shaded growing to avoid the heat of late summer. The fall harvest is as tasty as the spring one, although smaller volume. Row covering for managing the temperatures of early spring and fall may be appreciated.

In my opinion, the best performing varieties overall in this trial were Buttercrunch and Red Salad Bowl. Buttercrunch survived both of the shoulder seasons, as well as summer heat with an excellent taste and volume. Red Salad Bowl starts out as rather spindly seedlings, but once they are established, a mature plant will easily fill a salad bowl, as its name suggests. When some plants are removed for early meals, the final spacing for maturing plants of this variety can easily be 15 inches or more!

This trial has demonstrated that lettuce is not just a springtime vegetable. With careful and consistent attention to shading and watering, a modest crop is possible even in midsummer, and a fall crop can be as tasty as the spring. The Master Garden is not close to my residence, so I could not tend it as frequently as I can at home, where I was able to have four consecutive crops of lettuce in my raised bed this year, using the same varieties as in the Master Garden.