Freeze-Sensitive Plants in Palm Beach County (and South) What to Protect + How to Protect It

~ by Robert Hintze

Palm Beach County and the counties south of it usually enjoy mild winters, but a few cold nights each season can still cause major landscape damage, especially when temperatures drop quickly after warm weather. UF/IFAS notes that sudden freezes often do more damage than freezes that happen after plants have gradually acclimated.

Below is a practical, Palm-Beach-friendly guide: which plants are most at risk, when to take action, and proven protection methods that homeowners can do in an afternoon.

Know your “action temperatures” (so you don’t overreact or react too late)

Cold-sensitive (chilling) injury: Some tropicals can be stressed well above freezing.
Freeze danger zone: When temperatures approach 32°F, plan to protect tender plants.
The National Weather Service generally issues:
- Freeze Warning: temps forecast below 32°F within 24 hours
- Hard Freeze Warning: temps below 28°F for 3+ hours (rare along the immediate coast, more likely inland/western areas).

Palm Beach tip: Coastal neighborhoods may stay a few degrees warmer than inland/western areas. If you’re west of I-95 or near open fields/wetlands, you’ll usually feel cold first.

The highest-priority plants to protect in Palm Beach County and south

1) Tropical ornamentals that commonly get scorched or defoliate

These are the “usual suspects” in South Florida landscapes:

Ixora (often drops leaves after a cold snap)
Crotons, Ti plants, orchids
Hibiscus (flower buds and tender growth are easily damaged)
Bougainvillea, mandevilla, other tropical flowering vines
Many tender palms (some tropical palms are more susceptible to cold injury)

2) Tropical fruit trees (and why “young trees” need extra attention)

If you have fruit trees, age and growth stage matter a lot.

Mango
- Mature trees can tolerate short dips, but young trees may be killed around 29–30°F
- Flowers and small fruit can be damaged around 40°F for a few hours
Avocado
- Many avocados perform best where it doesn’t freeze; cold tolerance varies by variety/ecotype
Banana
- Estimated: ~28°F injury; below 28°F can be fatal
- Even temps below ~60°F can cause chilling stress over time

3) Tender vegetables and annual flowers (especially if newly planted)

UF/IFAS includes tender vegetables and many flowers among plants that can benefit from protection. Examples mentioned include tomatoes, peppers, and flowers like begonias, impatiens, zinnias, pentas, etc.

How to protect plants from freeze damage (the methods that actually work)

Step 1: Prioritize (you don’t need to cover everything)

Protect in this order:

Potted plants (they get colder faster)
New plantings / young tropical fruit trees
Showy tropical ornamentals you don’t want to lose foliage on
Everything else

Step 2: Use covers correctly (most “failures” are from bad technique)

UF/IFAS recommends coverings like cloth sheets, quilts, plastic, or commercial frost cloth with an important warning: remove plastic during sunny days or ventilate so it doesn’t overheat underneath.

Best practice for covering:

Cover late afternoon/early evening (trap warmth as the ground releases heat overnight)
Make sure the cover goes all the way to the ground (this is huge)
Anchor the edges (rocks, bricks, landscape staples) so wind doesn’t steal your heat
Keep fabric from crushing blooms by using stakes/frames for delicate plants
Uncover in the morning once temps rise and sun hits the plant

Avoid: thin plastic touching leaves directly (it can transmit cold and cause burn, plus overheating the next day).

Step 3: Add gentle heat for “must-save” plants

UF/IFAS specifically mentions a simple method: putting a light bulb under a cover to provide warmth for ornamental plants.
(Old-school incandescent bulbs produce heat; LEDs generally don’t.)

Good candidates: prized orchids, a young mango, a favorite croton hedge section, etc.

Step 4: Protect roots with mulch (especially for borderline plants)

A mulch layer helps insulate soil and reduce radiant heat loss. UF/IFAS-style guidance commonly emphasizes mulching as part of cold protection.

How:

Apply 2–4 inches of mulch around the root zone (keep mulch a few inches off the trunk/stems to avoid rot issues)
For bananas and other “die back but return” plants, focus on protecting the base/rhizome

Step 5: Move containers + protect the pot itself

UF/IFAS warns that container plants are commonly injured by cold.

Do this:

Move pots into a garage, screened porch, or against the house (south/west side is often warmest)
If they must stay outside: wrap pots with a towel/burlap, group them, and cover the group to the ground

“What about watering or sprinklers?”

A safe, homeowner-friendly approach is:

Water the ground the day before a cold event so soil holds heat better overnight (avoid saturating to the point of runoff).
Turn off irrigation timers, so you’re not accidentally running water at the wrong time.

Some sources warn against using sprinklers casually for freeze protection because timing and conditions matter; misuse can worsen damage. (Commercial freeze-protection irrigation is a specific technique, but it’s easy to get wrong at home.)

After the cold snap: what to do (and what NOT to do)

UF/IFAS emphasizes that proper post-freeze pruning matters.

Do:

Wait to prune until you can see what truly died back (often days to weeks later)
Keep roots healthy: light watering, avoid heavy fertilizer until recovery begins

Don’t:

Immediately “shape up” blackened stems the next morning—dead foliage can actually protect lower tissue from additional cold events

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Quick “Freeze Night” checklist (Southeast Florida)

Bring in or group potted plants
Cover ixora/croton/hibiscus/orchids and other tender ornamentals
Protect young mango/avocado/banana plants (cover + mulch; consider gentle heat for young mango)
Anchor covers to the ground
Uncover in the morning and ventilate if using plastic