Growing Lettuce in Summer

A juicy salad is just what we want in summer. But growing it can be a challenge:
Lettuce seed goes dormant in hot weather; often the seeds either don't sprout or come up unevenly. When you do get lettuce plants, they often turn bitter, or stop making leaves and just elongate into a flower stalk (this is called bolting.)

Lettuce is naturally a spring crop, adapted to cool soil and short days. But people love lettuce, and over the years, gardeners and farmers have learned how to grow it in summer.

Here are tricks to grow summer lettuce. The more of them you use, the easier it will be to harvest salads all summer.

• Not all lettuces grow well in summer. Choose varieties adapted to hot weather and longer days. Top picks: Jericho Romaine, Grandpa Admire's Redleaf, Emerald Fan Romaine Outredgeous Red Romaine,  Quan Yin Crisphead, and Bronze Arrow Oakleaf.
• Put lettuce seed packets in the fridge for a week before planting. When they come out, they'll think it's spring instead of summer. For long-term seed storage, use a jar or container with an airtight seal like a canning jar or sealable plastic box. It's a good idea to put in something to keep the air dry, like a silica gel pack, cat litter, or a cracker that you replace weekly.
• Sow seed at evening, water well, and keep flats in a shady place. Get the seedlings used to full sun gradually. Hardening to bright sun and heat is just like hardening-off seedlings to cold nights in spring--do it a bit at a time.
• Select a spot that has dappled sun, or morning sun with afternoon shade. That could be a less-sunny part of the garden, containers placed in semi-shade, or a sunny garden bed beneath a taller crop like pole beans. Or use shadecloth. A tub, trough, or set of larger pots on the porch, under trees, or near a door with afternoon shade will give you a nice salad garden. Watch out for slugs and snails in this shadier, moister environment.
• Fast growth is juicy, sweet growth. Work in compost before planting, keep soil moist, mulch well. If using potting mix, look for one with earthworm castings in it, and a pleasant texture. Avoid those with artificial chemicals, chunks of wood, and  other short-cuts. Black Gold Organic is widely available and works well for lettuce. Avoid mixes with huge amounts of perlite, which will have fewer nutrients and need watering more often.
• Add other greens that aren't so picky about temperature. Heat-tolerant greens include purslane, mizuna, vitamin green, yukina, arugula, and baby chard. Salad herbs include dill, chervil, parsley, basil, tulsi, cilantro, or fennel
  

The Summer Salad Collection bundles 3 summer-adapted lettuces with another salad green and a salad herb. Easy.