Lima beans are a warm-season classic: buttery, protein-rich and generous in a tropical garden, where they love the heat and the long season. In Zone 12 they are one of the most rewarding legumes, and as a bonus they fix nitrogen in the soil for whatever follows them. This guide tells you exactly how to grow them: when to sow, how to start seed, what soil and spacing lima beans need, how to water them, which neighbours help, which pests to watch, and when to harvest. Zone 12 is frost-free, with average winter lows of 50 to 60°F, so there is no last or first frost date to plan around — here you plant by heat and by the wet and dry seasons, not by frost. See the full planting calendar for the whole year, and check your local extension service for advice specific to your area.
Lima Beans at a glance in Zone 12
All figures below are broad published ranges from standard horticultural references, not exact figures for any variety or garden — they vary by variety, climate and soil. Use them to compare crops and to plan, not as promises.
| Detail | Lima Beans |
|---|---|
| Days to germinate | 7–14 |
| Days to maturity | 60–90 |
| Spacing (inches) | 4–6 |
| Soil pH | 6.0–7.0 |
| Sun | full sun |
| Sowing method | direct sow |
| Cold tolerance | tender |
| Water needs | moderate |
When to plant lima beans in Zone 12
Sow lima beans in the warm season — roughly March in most Zone 12 areas — when the soil is warm, since lima beans are more cold-sensitive than other beans and will rot in cool, wet soil. The published maturity range is 60–90 days, and the plants need warm weather for the whole of that time. Because Zone 12 is frost-free, you can sow whenever the soil is warm; avoid sowing right at the start of the heaviest wet season, when waterlogged soil can rot seed before it germinates. Check your local extension service for the best sowing window in your exact area. Our March in Zone 12 guide shows what else to sow that month.
Starting lima beans
Sow lima bean seed directly where it is to grow — beans do not transplant well. Germination takes 7–14 days in warm soil. Sow about an inch deep, space seeds 4–6 inches apart, and give pole varieties a strong trellis, fence or poles to climb; bush varieties need no support but still appreciate room. Do not soak the seed before sowing in wet tropical soil, since it can rot. Water in well and keep the soil moist until seedlings appear. The germination time calculator helps you plan sowing dates. Thin or transplant sparingly — beans resent root disturbance.
Soil, spacing and sun
Lima beans need light, well-drained soil with a soil pH of 6.0–7.0. They are not heavy feeders: too much nitrogen produces leaves at the expense of pods, so go easy on fertiliser and let the beans fix their own nitrogen. Work in compost before sowing, but avoid fresh manure. Good drainage is essential — beans rot in waterlogged soil, so a raised bed is the safest choice in wet tropical areas. Full sun suits lima beans; they need heat and light to pod well. Mulch once the plants are up to hold moisture and suppress weeds.
Watering and feeding
Lima beans need moderate, steady water. Keep the soil evenly moist while the plants establish and the pods fill — dry spells cause flowers to drop and pods to stay small. Water at the base in the morning, and avoid wetting the leaves, which invites disease in humid tropical air. In the dry season, a deep soak once or twice a week is better than daily sprinkles. Mulch helps enormously, holding moisture in the dry season. Do not overwater once pods are filling, since wet pods rot and the plants are prone to disease in standing water.
Companion planting
Good companions for lima beans are marigolds, basil, onions and lettuce. Marigolds at the bed edges may help deter soil pests. The classic Three Sisters planting — beans with corn and squash — works well in Zone 12, since the corn provides a living trellis and the squash shades the soil. Basil is a useful general companion. Avoid planting lima beans next to onions or garlic, which can stunt bean growth, and keep them away from other legumes in the same season. Rotate beans to a fresh bed each year. For another protein-rich legume from the same season, see our guide to Edamame in Zone 12.
Pests and problems
Watch for aphids, bean beetles, slugs and cutworms. Aphids cluster on tender new growth and can be washed off with water. Mexican bean beetles chew leaves and pods — check the undersides of leaves and pick them off by hand. Slugs love damp mulch around young plants; check at night and remove them by hand. Cutworms sever young seedlings at soil level; collars help. In humid tropical air, beans are also prone to fungal diseases, so give plants room for airflow, avoid wetting the leaves, and remove badly affected leaves promptly.
Harvest and storage
Harvest lima beans when the pods are plump and the beans inside are full-sized but still tender, usually within the published maturity range of 60–90 days from sowing. Pick regularly — the more you pick, the more the plant produces. For fresh eating, shell the beans and cook them promptly. For drying, leave the pods on the vine until they are dry and papery, then shell and store in a cool, dry place. Eat fresh beans within a few days, or freeze them after blanching. Lima beans are excellent in soups, stews and succotash.
Frequently asked questions
Are lima beans good for Zone 12?
Yes — they love heat and long seasons, and they fix nitrogen in the soil. Sow in the warm season when the soil is warm, and give pole varieties a strong trellis.
Should I soak lima bean seed before sowing?
No, not in Zone 12. Soaked seed rots easily in warm, wet soil. Sow dry seed about an inch deep and keep the soil moist but not waterlogged.
Why did my lima beans not germinate?
Usually soil that is too cool or too wet. Lima beans are more cold-sensitive than other beans and rot in cool, wet soil. Wait until the soil is warm and improve drainage.
How do I store dried lima beans?
Let the pods dry fully on the vine, shell the beans, and store them in a cool, dry, airtight container. Properly dried beans keep for months.