A broad bean plant covered in leaves and flowers but carrying few or no actual pods almost always comes down to pollination rather than a genuine fault in the plant. Broad beans self-pollinate but lean on bees for reliable cross-pollination too, and they need pollen to form inside a fairly narrow temperature band — so weather at exactly the wrong moment, not the plant's health, is usually the real explanation.

What's Most Likely Going On

  • Bees weren't active when the flowers needed them. Wet, windy conditions keep bees grounded, and flowers left incompletely pollinated in that window often still form a pod that blackens and drops rather than fills out. This is the leading cause of an otherwise healthy, pest-free plant coming up short.
  • A nutrient gap or soil sitting too wet. A plant that's short on feed, or rooted in ground that can't drain, can flower heavily without carrying any of it through to pods — worth checking once weather itself seems settled.
  • Heavy blackfly pressure, covered separately in Why Are My Broad Beans Covered in Blackfly in NZ Sub-Tropical? — a visible aphid colony changes the diagnosis, so rule pests in or out by eye before settling on pollination as the cause.

Cold Is Almost Never the Story in This Zone

Broad beans follow the exact same August-to-October sowing and December-to-February harvest window in every NZ zone, and this particular zone's frost season is the shortest of the three by a wide margin. That near-absence of cold effectively rules out the pollen-temperature failure that drives this problem further south — flowers here reach a workable pod-set temperature earlier and more reliably than anywhere else in the country. Which means if pods genuinely still aren't forming, the far more likely explanations are wet or humid weather keeping bees from working, or waterlogging, given how much more rain this particular zone typically gets than either other one.

Fixing It

  • Wait out a wet or humid stretch rather than assuming the season's a loss. The plant keeps flowering, and once bees are back out, later flowers generally set without issue.
  • Plant something bee-attracting nearby so pollination has the best odds once weather stops being the obstacle.
  • Clear away pods that have already blackened, freeing the plant's energy for the next round of flowers rather than holding onto ones that failed.
  • Feed with a complete fertiliser if plants look pale or slow alongside the missing pods — Yates NZ points specifically to a fish and seaweed-based feed for this crop.
  • Check drainage if the bed's been consistently wet, since broad beans need workable drainage to take up nutrients even mid-flower.

Cultivar Notes

The cultivars sourced for this zone — Coles Prolific, Red Seeded, Scottish, Superaguadulce and Suttons Dwarf — are documented for sowing method and timing, not pollination performance, so a variety switch won't fix this problem on its own. Weather at flowering carries far more weight than which cultivar is in the ground.

Next Season

Given how rarely cold plays a role here, a consistently patchy pod set is worth tracing back to whether flowering lands during this zone's wettest or most humid stretch rather than anything to do with the calendar itself — a small shift within the August–October sowing window might move flowering clear of it, though that's worth testing in your own garden rather than assuming it'll hold every year.

More on this zone: see the full NZ Sub-Tropical Planting Calendar →.