Is there a plant which can withstand heat up to 40 degrees Celsius?

Question

There are many plants recommended over the internet as heat tolerant plants. I am not sure how much heat they are talking about.

My Habanero Chili peppers are in bad shape due to the heat wave coming from the air conditioner downstairs. Now I am looking for a new plant suitable to this condition. The temperature varies from 30 to 40 degrees Celsius (85 to 100 Fahrenheit). Although 40 is rare, it is not uncommon to see 35 degree Celsius.

Are there any plant recommendations other than cactus? I don't want cactus because they grow slowly.

Answer 1

Those sound like the kind of temperatures we get here in North Texas (today will probably hit 40C - we have a hot week forecast!). Every summer for the last 10 years I've grown peppers in those conditions. Peppers are adapted to heat stress, so they'll appear to wilt during the day (leaves turn floppy like thin paper) but will perk up with a good watering. So give them a good watering each evening.

Also, peppers usually stop producing fruit during those conditions. There will be flowers, but no fruit. We get fruit in late spring/early summer (May to June) and then the main crop September-November. By watering the peppers during the summer, the plants grow good stems and leaves - ready for fruit production in the cooler months.

I have had some exceptions in recent years. Last year "Gypsy" (smaller, yellow bell pepper) was very prolific with lots of fruit throughout summer. Also this year, I'm still getting fruit on my peppers (new house, and the bed is probably particularly good nutritionally) - varieties are: Cayenne, Pimento, Big Jim (Anaheim), and Sweet Banana.

re. @Rory's suggestions: There are cacti for all temperatures (some grow in the wild in Canada) - the main requirement is good well draining soil. Prickly pears are particularly easy to grow and cuttings are very easy. We have some zinnia I sowed back in March and we now have flowers, and they don't appear to be wilting.

Do you have water and humidity? If so, consider tropical plants. We have bananas with fruit on them - in North Texas! (the books describe it as rare for south Texas and don't even both with the possibility up here due to our frosts). In a tropical environment, bananas will provide some shade and bring in lots of animals and birds.

Answer 2

You can see from this site that Habaneros like a temperature of between 60 and 90 Fahrenheit, which is 15 to 32 Celsius, so you are exceeding that.

There are a wide variety of cactuses, and some grow faster than others, so you could have a look at the varieties available to you.

While cactuses may not be your thing, a useful way to find suitable plants might be to search for plants which survive in Texas or other hot climates, eg:

• Blackfoot Daisy
• Mexican Zinnia
• Cigar Plant

Answer 3

I hope you can make sure night-time temperatures are enough cooler than in the daytime. That air-conditioner has me concerned.

Anyway, without more information about that, here's what I would say:

C. Chinense peppers seem to like more moderate conditions than some other kinds of peppers. If you want to grow a Habanero-like pepper that can do well in extreme heat, I recommend Aji Habanero. It's C. Baccatum and it grows well in my area where I've had trouble with C. chinense peppers (in part, I assume, due to the heat; it's not rare for it to get above 40°C. in the summer (although we don't have much humidity at all and things can dry out fast).

I recommend growing peppers either in the ground with mulch (e.g. pine bark mulch), or in containers. Either one seems to make a big difference for me. I like to use 10-gallon totes (that's what I used for Aji Habanero).

As for other suggestions, I might recommend trying Sweet Banana Peppers, Louisiana Long Pod okra, Sausage tomatoes, Brandy Boy tomatoes, Sweet Orange Cherry tomatoes, Torpeda melons (and some other muskmelons), West India burr gherkins, summer savory, basil, sunflowers, Jerusalem artichokes, Elberta (I think) peach trees, nectarines, Stanley Plum trees, sorrel (if you shade it), and other stuff. These are all things that have done well in the heat for us, anyway. You might also try horseradish.