Because most lettuce is self-pollinating its easy to save seeds that will be exactly like the parent plant. Choose one of your best lettuce plants, don't pick it and keep watering & feeding it until it flowers. (You can pick some of the outside leaves for eating without harming seed production.) Lettuce sends up a tall branching flower stalk topped with small yellow daisies. Harvest the entire stalk when the seeds are ripe - about two to three weeks after flowering. Hang it upside down inside a paper bag in a dark, dry place for a few days until completely dry. Store in an airtight container in a dark place until next year.
Colourful Lettuces for Containers:
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Brunia
A red oakleaf lettuce with amazing flavour. Large heads hold up well in the summer heat. Ruby wine colour looks great on the balcony garden. Space 6 in./ 15 cm. apart in containers.
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Tom Thumb
This teeny-tiny butterhead (boston-style) lettuce dates back to 1853. It's a very early variety with deliciously soft leaves. Each head makes a tiny salad for one person. Perfect for container gardening - should be spaced 2-3 in./ 5-7 cm. apart.
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Black Seeded Simpson
An 1850 heirloom leaf lettuce, with light green crinkly cut leaves. Good mild flavour, matures early, great yields. As with most leaf lettuces, if you keep picking the outer leaves, the plant will continue to produce foliage until it finally flowers. Space 8 in./ 20 cm. apart in containers.
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May Queen
A medium-sized, mild-tasting butterhead lettuce. Pale green heads are tinged with red. Can tolerate early spring plantings - matures in 45 days so perfect for the Ottawa area. Space 8 in./ 20 cm. apart in containers.
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Merlot
A Bibb-type lettuce with unusual deep burgundy leaves with ruffled edges. One of the most beautiful red lettuces I have grown - the colour holds all summer. Tolerates hot humid summers - very slow to go to seed. Space 6 in./ 15 cm. apart in containers.
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Drunken Woman
This large Italian Heirloom butterhead lettuce has gorgeous bright green ruffled leaves with a hint of bronzy-pink at the leaf margins. Crisp texture, sweet taste, and very slow to bolt. Space plants at least 12 in./ 30 cm. apart in containers.