August 29th column: Warmth Tolerant Greens

These ‘Tuscan Napoli’ melons grow in our tire house.

After the scorching summer we experienced, I thought it would be wise to research heat tolerant vegetables. Will the extreme heat and drought conditions be the “new normal” for us? Well, it never hurts to plan ahead, does it?

That is the topic of today’s garden column, which you can read in The speaker review: Some vegetables can withstand the summer heat. (or you can read it under the videos below)

I was interested in finding the variety names of heat tolerant vegetables. There are many that I will be happy to try next year. Do you have any recommendations? I would like to hear from you. Just send an email to [email protected]

In this week’s video, I show Step 2 of my three-step pruning process for ripening green tomatoes. Two weeks ago I covered Step 1 and will be adding this video below this week’s. I live in Spokane, Washington where the hardiness zone is 5b / 6. I usually start my tomato pruning around 6 weeks before our average first frost date. In two weeks I will cover the third and final step. I will also talk about additional ways to ripen green tomatoes.

Here is the text of my column on heat tolerant vegetables:

By Susan Mulvihill
For the speaker review

I’m not sure if our hot, dry summer has any more unpleasant surprises in store for us, but I’m definitely thinking about how we can have a more successful vegetable garden in 2022.

I’ve had mixed results in this year’s garden. The pumpkins, zucchini, and winter squash didn’t seem to bother the intense heat and produced well. The melons and sweet potatoes that grow in our tire house are developing splendidly. I’ve kept both doors open so they don’t get too hot and pollinators have access to the melon flowers.

Before our heat wave at the end of June, the corn had grown by leaps and bounds. After a few days with temperatures in excess of 100 degrees, the tallest leaves of each corn stalk were burned crispy. The plants stopped growing but produced our earliest – and smallest – harvest ever. The always reliable runner beans produced far more short, curly beans than the long, lean beans we would expect.

The tomato plants stand still for a few weeks: no flowers, hardly any fruit and there are many signs of blossom end rot. About half of my varieties of carrots are screwed with seeds.

What does a gardener do? Look for more heat tolerant plants and varieties that may perform better if we encounter similar conditions next year.

From my research, most green beans don’t tolerate excessive heat very well. Two Pole varieties that show potential, however, are ‘Rattlesnake’ and ‘Fortex’. French beans also have a good reputation.

I have read of a few varieties of tomatoes that are said to do well in hot, dry climates, but I have no experience growing them. These include Arkansas Traveler, Grand Marshall, Great White Beefsteak, Marvel Stripe, Purple Calabash, Solar Flare and Summer Set.

One of my Facebook followers recently suggested that if our future summers are as hot and dry as this year, varieties of corn grown in the Midwest might be worth trying. My research resulted in varieties like ‘Bodacious’,’ Honey ‘n Pearl’, ‘Illinois Xtra-Sweet’ and ‘Kandy Korn’.

Most varieties of spinach will turn into seeds as soon as summer temperatures rise. I don’t think there are traditional varieties out there that would withstand the heat we experienced, but there are some alternatives that don’t include spinach. Malabar spinach leaves have a similar taste and grow on attractive vines. Red Orach also tastes like spinach and has beautiful purple-red leaves. New Zealand spinach has juicy stems and leaves that give it heat tolerance.

I wish there were types of lettuce that wouldn’t go away in hot weather. There are some that are slower to shoot – like ‘Cherokee’, ‘Muir’, ‘New Red Fire’ and ‘Salvius’ – but all salads tend to get bitter in the heat.

Have your cucumber vines struggled this summer? I recently learned that Armenian cucumbers grow and produce wonderfully in hot conditions. They’re technically melons, but they taste like cucumber and don’t turn bitter. It might be fun to try them out next year.

If you’re growing hot peppers this year, I should give you a warning. During normal summer, some gardeners cut down the water to produce more flavorful peppers. With our excessive heat and drought, you might be in for a big surprise!

No matter what you grow in the summers to come, I believe a little trial and error is in order and I would love to hear which plants and strains work best for you.

Susan Mulvihill is the author of The Vegetable Garden Pest Handbook. She can be reached at [email protected] Check out this week’s Anyone Can Grow a Garden video at

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