Cowpea, also known as the black-eyed pea, is a genuinely drought-tolerant warm-season legume grown here for dried storage, per the crop database's own description. It's self-pollinating with low outcrossing under normal conditions, but its one real cross-partner on this site isn't a lookalike relative -- it's yardlong bean, which is the same species entirely.
Water need
Genuinely drought tolerant once established -- one of the more forgiving legumes on this site for a dry warm season.
Calories at a glance
3,360 kcal/kg dried -- a genuine calorie staple, in the same league as the site's other dried pulses (scale is log-based across all 55 core crops in the calculator).
Temperature Range by Month
Month on the bottom, temperature up the side. The pale green background is what the plant can survive at all -- fatal above or below it, labelled directly on the chart where that applies to your zone. The coral band is its ideal range, and only fades in during the months this zone would actually have the crop in the ground -- reusing the exact same sowing/harvesting data as the calendar further down the page. The blue line is real monthly climate data (not a modelled estimate) for a representative rural/agricultural location in this zone -- a small farming town or agricultural research station rather than a major city, to avoid the warmer bias city weather stations have. For the actual verdict on how well this crop does in your zone, see the badge at the top of the page -- that's based on the site's own researched yield figures, not this chart.
Quick Start: Sowing to Drying
- Sow direct once the soil is warm. Sow seed direct after the soil has genuinely warmed -- cowpea is a true warm-season crop and germinates poorly in cold ground.
- Keep young plants watered until established. Water while plants establish; once rooted in, cowpea's real drought tolerance takes over and it needs little further irrigation.
- Let most pods mature for drying. Leave the bulk of the crop's pods on the plant until they dry and rattle, rather than picking them young for fresh eating.
- Harvest before pods shatter. Pick dried pods promptly once ready -- cowpea pods can split and drop seed if left too long past full dryness.
- Shell and finish drying indoors. Shell the pods and spread the beans somewhere warm and airy for a final week of drying before storing in an airtight container.
Sowing & Harvesting Calendar
Pick your zone under "Temperature Range by Month" above and this updates too. Boreal and Alpine show no window at all, since this site's own yield data marks cowpea as not viable there.
Calories & Yield
Cowpea is a genuine calorie staple when dried at about 3,360 kcal per kg -- Tropical gives the best yield here, and it's not viable at all in Boreal or Alpine zones.
| Climate Zone | Yield per plant | Calories per plant | Viability |
|---|---|---|---|
| Tropical / Humid | 3.0 kg | 10080 kcal | Viable -- best yield |
| Subtropical | 2.5 kg | 8400 kcal | Viable |
| Mediterranean | 2.0 kg | 6720 kcal | Viable |
| Temperate Maritime | 0.6 kg | 2016 kcal | Challenging (60% yield) |
| Temperate Continental | 0.9 kg | 3024 kcal | Challenging (60% yield) |
| Cool / Boreal | -- | -- | Not viable |
| Arid / Semi-Arid | 2.0 kg | 6720 kcal | Viable |
| Highland / Alpine | -- | -- | Not viable |
Figures per plant sown, dried weight, from the site's own crop database. Maritime and Continental already reflect the 60% penalty applied to challenging zones.
Varieties Worth Knowing
Cowpea (black-eyed pea) varieties differ in seed colour and disease tolerance. All the varieties below are open-pollinated (OP), meaning seed saved from them breeds true and is worth keeping under this site's seed-saving approach; none are F1 hybrids.
Seed Saving -- Quick Guide
Cowpea crosses with yardlong bean and honey bean -- all the same species (Vigna unguiculata) -- but not with common bean or other Vigna species like mung bean or black gram.
SERVINGS, NOT DAILY CALORIES This works out plate-sized servings of cowpea from your seed during its fresh harvest window only, not your group's full daily calorie needs. For that, use the main calculator.
Estimated for your selected zone above, using this site's own germination, loss and yield figures for cowpea -- a helping is roughly what you'd put on a plate as part of a meal with other veg. Treat it as a planning estimate, not a promise.
Storage & Preservation
Cowpea is grown here specifically for dried storage, though the crop database notes it can also be eaten fresh -- pods left to dry fully are shelled and given a final week of airing indoors before going into an airtight container.
Stored this way in a cool, dry place, dried cowpea keeps for a genuinely long time -- years rather than months, the same storage league as this site's other dried pulses.
Growing Cowpea Without Bought Inputs
Cowpea's genuine drought tolerance is itself an input-free advantage -- it keeps producing through dry spells that would demand irrigation for less resilient legumes.
Aphids and bean beetles are the main pests to watch for, especially on young growth -- hand-picking or a strong water spray usually keeps light infestations in check without spraying.
Cowpea fixes its own nitrogen via bacteria in root nodules, genuinely improving the soil for whatever's grown there next -- factor that into a wider rotation plan, not just a calorie one.
Frequently Asked Questions
Does cowpea cross with yardlong bean?
Yes -- genuinely so. Cowpea and yardlong bean are the same species, Vigna unguiculata, with yardlong bean simply being subspecies sesquipedalis. If you grow both, treat them as a same-species cluster and isolate them from each other exactly as you would two varieties of the same crop.
Does cowpea cross with any other bean on this site?
No -- cowpea is Vigna unguiculata, a different genus from common bean, runner bean and broad bean. Yardlong bean is the only real cross-partner, because it's the same species rather than merely a relative.
How drought tolerant is cowpea really?
Genuinely drought tolerant, per the crop database -- it's a warm-season crop bred for reliable pod set even under moisture stress that would knock back most other beans, though it still needs a real warm season to perform.