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Best Counties for Tropical Plants

Published May 2, 2026

Tropical and subtropical plants — citrus, bananas, hibiscus, bougainvillea, and mangoes — require hardiness zones 10 and warmer to survive winter outdoors. These plants demand soil that drains well yet retains enough moisture, and they benefit from the active soil biology that year-round warmth sustains.

We identified the counties where tropical plants can thrive outdoors, ranked by zone warmth and winter minimum temperatures.

Best Counties for Tropical Plants

Broward County, FL in zone 11a offers the warmest winters for tropical gardening in the United States.

RankCountyStateZoneMin Temp (°F)
1Broward CountyFL11a40
2Miami-Dade CountyFL11a40
3Monroe CountyFL11b45
4Yuma CountyAZ10a30
5Alameda CountyCA10a30
6Imperial CountyCA10a30
7Los Angeles CountyCA10b35
8Marin CountyCA10a30
9Orange CountyCA10b35
10Riverside CountyCA10a30
11San Bernardino CountyCA10a30
12San Diego CountyCA10b35
13San Francisco CountyCA10b35
14San Luis Obispo CountyCA10a30
15San Mateo CountyCA10a30
16Santa Barbara CountyCA10b35
17Ventura CountyCA10a30
18Brevard CountyFL10a30
19Charlotte CountyFL10a30
20Collier CountyFL10b35
21Glades CountyFL10a30
22Hendry CountyFL10a30
23Indian River CountyFL10a30
24Lee CountyFL10b35
25Manatee CountyFL10a30

Soil Tips for Tropical Gardens

  • Amend with compost regularly — tropical plants are heavy feeders due to year-round growth.
  • Ensure excellent drainage — many tropical plants suffer root rot in waterlogged soils.
  • Mulch heavily to maintain even soil moisture and temperature in the root zone.
  • Test pH annually — many tropical plants prefer slightly acidic soils (pH 5.5-6.5).

Methodology

Counties in USDA hardiness zones 10 and warmer, ranked by zone number. Data from USDA PHZM 2023.

Data sourced from USDA Plant Hardiness Zone Map (2023) and USDA SSURGO Soil Survey. Hardiness zone data represents average annual extreme minimum temperatures and should be used as a general guide. Local microclimates may vary significantly from county averages.

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