Cold protection of tropical container plants

Q: I am long time customer of yours, I live in San Diego California and while the summer and Fall temperatures are warm to mild, the winter temperatures dip to a point where some tropicals die off. We are experimenting with different variations of way to heat and insulate the pots we have the tropicals planted in as a way to keep them alive during the colder winter months. I was wondering if you knew of the ideal soil temperature for these tropical in order to look their best year round. All of the heaters we have installed have thermostats and temperature adjustments so we can now keep the soil anywhere between a range of between 65-75 degrees. Any advise you can provide would be greatly appreciated.

A: This is a very interesting concept you are working with. Indeed, keeping pots/roots warm, may help a lot! We've been experimenting with cold protection for a long time - for the above-ground plant parts. For sure keeping roots protected (even with a thick layer of mulch) will benefit tropical plants during winter. In case with container plants, this may help dramatically.
The guideline is, tropical plants slow down or stop their metabolism at 65F. As long as you can keep soil above that temperature - this should work great. Of course, the higher the better.
Optimum temperature for growing tropical plants in general - 70-85F. Above 90F, metabolism stops too, unless it's a heat tolerant, desert plant.

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About Cold Protection
Cold protection - winter action for your plant collection
Tropical Treasures articles on zone pushing.

New Year with New Plants:
Choose from 17 Tropical Paradise Resolutions!

"A garden is never so good as it will be next year..." - Thomas Cooper.

Happy New Year, dear fellow gardeners! As we step into a fresh new year, it's the perfect time to think about what exciting, special, and life-changing plants we can add to our gardens. The days are getting longer, and spring is just around the corner, so now's the time to make a plan and prepare for the season ahead. Let's take small steps each year to create the garden of our dreams. This winter, consider these fun resolutions:

1. Hang a bird feeder and install a rain barrel
2. Order some tropical plant seeds for an early start
3. Ask your grandparents about their favorite garden plants
4. Build a raised bed for succulents
5. Plant a fruit tree or two to have some crop this year
6. Start a compost pile
7. Switch to organic fertilizers and plant boosters
8. Fill empty spaces with flowering trees, shrubs, and vines
9. Add butterfly attractors to your garden
10. Provide water for bees and butterflies to help them thrive and pollinate your fruit trees
11. Get a bonsai starter to try bonsai art
12. Enjoy meals outside as often as you can
13. Teach a child how to plant a tree
14. Plant berry-bearing shrubs like Tropical Cherries to feed the birds
15. Rake up leaves for winter mulch
16. Add a few exotic plants to your indoor collection or container garden
17. Share plants as gifts all year long

Happy gardening in 2025!

The Robuster: smart and simple
Automatic care-free plant feeder!

Affordable Smart Fertilizer Injector and Doser

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The Robuster.
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Let The Robuster do the feeding so you have more time to enjoy your garden! Your first gallon of Sunshine Boosters is available to you at a 50% discount with the purchase of this unit! Sunshine Boosters are also available at deep discounts with our subscription program (coming soon). Contact us for more information.

Developed in Ukraine. Manufactured in the USA.
Introductory low price! Only 4 units available at this time.
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Learn more:

Blog: About The Robuster with pictures
Amazing video:

Starter gardens at TopTropicals as well as container plants, are fertilized with the Robuster with every watering