Limes are the lemon's tropical cousin, and if anything they suit Zone 12 even better. Key limes, Mexican limes and Tahitian limes all grow outdoors year-round in the tropics, fruiting heavily with almost no fuss. If you cook with lime, make drinks, or just love the scent of a lime tree in flower, one tree is all you need.
Like every crop in the tropics, limes rewards gardeners who work with Zone 12's seasons — the cooler, drier months and the hot, wet months — rather than against them. The planting calendar hub gives the Zone 12 picture month by month, and our guide to when to plant limes in Zone 11 shows how the timing shifts in a cooler zone.
Zone 12 at a glance
USDA Zone 12 covers the warmest, most tropical parts of the United States — Hawaii, Puerto Rico, Guam and the U.S. Virgin Islands. Winters are warm, with average winter lows of 50 to 60°F, and the growing season never really ends.
Zone 12 is frost-free year-round: there is no average last spring frost and no average first autumn frost. That means you plant by heat and by the wet and dry seasons, not by frost dates. These are USDA zone averages, not exact figures for any one garden — always check your local extension service and the forecast before planting.
| Detail | Zone 12 guidance |
|---|---|
| Average winter low | 50 to 60°F |
| Average last spring frost | Frost-free (no frost dates) |
| Average first autumn frost | Frost-free (no frost dates) |
| Days to germination | 14–28 days |
| Days to maturity | 1095–1825 days |
| Sowing | start indoors or direct sow |
| Sun | full sun |
| Soil pH | 5.5–6.5 |
| Spacing | 120–180 inches |
| Water needs | moderate |
| Cold tolerance | tender |
When to plant limes in Zone 12
Plant limes in Zone 12 in spring or early summer, at the start of the warm, wet season, when the soil is warm and rain will help young trees establish. Because Zone 12 is frost-free, with winter lows of 50 to 60°F, there is no frost date to wait for — any warm month with reliable moisture will do, and trees planted in spring get a full growing season before the cool months. Trees take 3 to 5 years to fruit. Check your local extension service for the best local planting window. See the Zone 12 March planting guide for what else to plant that month.
Starting limes in Zone 12
Start limes from grafted nursery trees — seed germinates in 14–28 days but will not come true to variety and takes many years to fruit. Buy a grafted tree of a variety suited to your area, such as a Tahitian lime or a Key lime, and plant it in spring, spacing trees 120–180 inches apart. Limes also grow well in large pots, which is ideal if space is limited. Dig a wide hole, enrich it with compost, and water well after planting. The plant spacing calculator can help you plan the layout.
Soil, spacing, sun and water
Limes need full sun and well-drained soil with a pH of 5.5–6.5. They will not tolerate waterlogged roots, so in Zone 12 plant on a slight mound or in a raised area where the rainy season drains away. Water needs are moderate — water young trees regularly for the first two years, then water deeply in dry spells, and mulch thickly to keep roots cool and moist. Feed in spring and summer with a citrus fertiliser, since limes are hungry trees.
Companion planting
Good companions for limes include borage, marigolds, clover and chives. Clover under the tree fixes nitrogen and acts as a living mulch, marigolds deter soil pests, and borage attracts pollinators that improve fruit set. Keep limes away from grass right up to the trunk, and do not plant anything that needs constant watering under the tree. The companion planting finder can suggest combinations for your whole bed.
Pests and problems
The common pests to watch for with limes are aphids, slugs and cutworms. Aphids cluster on young shoots — wash them off with water. Slugs nibble young trees in wet weather; keep mulch away from the trunk. Cutworms can damage young transplants at soil level. Citrus in the tropics can also suffer from leaf miners and scale; prune for air flow, keep the tree healthy, and check the undersides of leaves regularly.
Harvest and storage
Harvest limes 3 to 5 years after planting, once trees are mature — and then expect fruit for much of the year, since limes in the tropics fruit over a long season. Pick Key limes when they turn yellow and feel soft, and Tahitian limes when they are full-sized, dark green and slightly soft. Cut fruit with secateurs rather than pulling it. Eat fresh, juice them, or preserve them; limes keep for weeks in a cool place.
Key lime vs Tahitian lime in Zone 12
The two limes most gardeners choose between are Key limes and Tahitian limes, and they suit different gardens. Key limes, also called Mexican limes, are small, seedy and intensely aromatic — the lime of Key lime pie — and the tree is thorny and bushy. Tahitian limes, also called Persian limes, are larger, seedless and milder, and the tree is thornless and more upright.
In Zone 12, both grow well, so choose by taste and by space: Key lime for flavour and for pies, Tahitian lime for easy picking and everyday cooking. Many gardeners grow one of each, and a household with two lime trees will never buy a lime again.
For a related crop, see our guide to when to plant lemons in Zone 12.
Frequently asked questions
When should I plant limes in Zone 12?
Plant in spring or early summer, at the start of the warm, wet season, so young trees establish with the help of rain. Zone 12 is frost-free, so any warm month with reliable moisture works, and trees take 3 to 5 years to fruit.
Do limes grow well in Zone 12?
Yes — limes are one of the most reliable fruits in the tropics. They grow outdoors year-round, fruit heavily, and need only sun, drainage and feeding.
When do I pick Key limes?
Pick Key limes when they turn yellow and feel soft. Tahitian limes are picked when full-sized, dark green and slightly soft.
Can I grow limes in a pot?
Yes — limes grow very well in a large pot with free-draining mix. Water well, feed monthly through the growing season, and move the pot to the sunniest spot.