When to Plant Lima Beans
Planting Window
- Direct sow
- Soil above 65°F, several weeks after last frost
| USDA Zone | Typical Window |
|---|---|
| Zone 5 and colder | Early June, favor a bush type |
| Zone 6-7 | Late May to early June |
| Zone 8 and warmer | Wide window; thrives in sustained heat |
Lima beans are a frost-tender legume that's genuinely fussier about soil warmth than common green beans - seed sown into soil that's merely warm enough for bush or pole beans often germinates poorly, and the plants themselves want sustained heat through the growing season more than most beans do.
Direct Sowing, Into Genuinely Warm Soil
Soil that's merely warm enough for bush beans often leaves lima bean seed sitting and rotting instead of germinating - waiting an extra week or two past the standard bean-planting window is a reasonable precaution in marginal conditions, since lima beans are genuinely fussier about soil warmth than their bush and pole relatives.
Bush and Pole Types Both Exist
Like common beans, lima beans come in both bush (more compact, faster, no support needed) and pole (vining, needs a trellis, generally longer total production) forms - the choice between them follows similar logic to choosing between bush and pole common beans, adjusted for lima beans' generally longer overall maturity window either way.
Baby vs. Full-Size Lima Varieties
Baby lima varieties mature somewhat faster and produce smaller beans than full-size (Fordhook-type) limas, which can matter in shorter-season zones trying to fit this already heat-hungry crop into a limited warm window - choosing a baby type over a full-size one is a reasonable way to improve the odds of a complete harvest where season length is tight.
Heat Tolerance Through Pod-Set, Not Just Germination
Beyond germination, lima beans handle sustained summer heat during flowering and pod formation better than common green beans, which can drop blossoms and stall pod-set during an extended heat wave - this makes lima beans a genuinely useful crop for gardeners in hot-summer regions looking for a legume that keeps producing when common beans are struggling.
A Later Flush Can Be Left to Dry
Lima beans left to dry fully on the plant, pods rattling and turning brown or tan, can be shelled and stored as dry beans for winter cooking or next year's seed - the same plant that produces a fresh green-shell harvest earlier in the season will finish a later flush as dry beans if simply left alone.
Zone boundaries follow the USDA Plant Hardiness Zone Map (2023 revision); frost windows reflect NOAA/NCEI climate normals. Both are typical historical ranges, reviewed annually - not a forecast or a guarantee for any single year. See Methodology & Sources.
Frequently Asked Questions
Does succession sowing make sense for lima beans the way it does for bush beans, or is one planting the practical limit?
One planting is the practical norm for most gardeners - lima beans already take considerably longer to mature than bush beans, and a plant left alone keeps flowering and setting new pods over an extended stretch rather than finishing all at once, so a single well-timed sowing usually delivers a longer harvest window on its own. Squeezing in a second sowing really only works in a long, hot-summer climate with enough season left after the first planting to actually finish a second round.
I'm in a cooler summer climate with a long enough frost-free season - will lima beans still struggle even without a frost problem?
Possibly, yes - heat during flowering matters as much as season length does. A long but persistently cool, cloudy summer, like parts of the coastal Pacific Northwest, can suppress pod-set even with months of frost-free days available, since the plant needs real sustained warmth while flowering, not just calendar time. Picking the warmest, most sheltered spot in the garden and waiting a little past the standard planting window for soil to warm further matters more here than season length alone.
Is there an actual flavor or texture difference between baby limas and full-size Fordhook types, or is speed the only reason to choose one?
There's a real culinary difference beyond speed - baby limas are smaller, more tender, and milder, the type most often used in succotash and mixed frozen vegetables, while full-size Fordhook limas are starchier and meatier with a more pronounced flavor once cooked. If season length isn't a constraint for you, that culinary difference is worth choosing on its own, independent of which one finishes faster.