Sustainably Yours: The Heat Tolerant Salad Garden

Living on the same line of latitude as Hawaii comes with obvious perks. As a gardener with northern origins, however, there are some adjustments to be made. These tweaks are most especially useful in the summer growing months.

The majority of traditional veg crops can grow quite happily during our cooler winter period. This perfect 3 month span, December through February, is the tropical equivalent of a perfect 3 month growing span during New England’s summer period. It’s fast but pretty perfect. Once the summer humidity rolls in, or even the soaring dry heat of the spring, the gardener’s palette of content veggies starts to change.

Today we will focus on heat tolerant greens. Most gardeners know that lettuce likes it cool – think UK, Beatrix Potter, lush and mild weather with lots of moisture. Lettuces especially do not like warm temperatures to germinate in – germination will be sporadic and disease prone. So it’s best to wait for the chillier weather of November to begin germinating – your later seedlings will more than outrace earlier versions sown in warm October. Otherwise, you carry on with new sowings every 3 weeks, for a continual harvest, similar to lettuce routines up north.

Come summer, you will need to adjust your strategy and/or selection. I have found three approaches to be very useful:

  • In the summer, switch to heirloom lettuce varieties bred for the humid Old South of the States. These oldies but goodies are simply more tolerant of high heat, sun and humidity, without growing bitter from the start. You have a chance at tender sweetness.
  • Grow aquatic edible greens. Floating in water not only prevents leaf cutter ants from decimating an all-they-can-eat buffet but the moisture saturation prevents bitterness due to heat stress.
  • Switch over to tropical perennial and alternative greens. The flavors vary but they’re an excellent option to get superfoods into your diet! These selections blow Iceberg lettuce away!

The following is a list to get you started. Remember, keep these greens out of direct sun and rain. See what you can get your gardening mitts on and enjoy those salads!

Heirloom lettuces:  • Jericho Romaine • Salad Bowl Green – Butterhead • Black Seeded Simpson • Simpson Elite • Prize Leaf • Freckles Romain • Little Gem • Mascara • Amish Deer Tongue

Aquatic greens that never get bitter. Invasive when in wild. • Water cress (pests love it, though), water spinach, water mimosa

Alternative and perennial greens • moringa • chaya (cooked) • malabar spinach  • cranberry hibiscus • basil  • indian lettuce   (lactuca indica) • ethiopian kale  • mustards  • collards • beet greens • turnip greens • buckwheat leaves  • amaranth leaves  • orach • katuk • tropical tree kale  • swiss chard • young sweet potato leaves  • microgreens and sprouts (indoors)

Emily Majewski