Squash and pumpkin
A crop with entirely separate male and female flowers, which means every single fruit requires an insect to carry pollen from one to the other — no pollinator, no squash. In the Americas it is served by a group of bees that specialise on it exclusively, the squash bees, which sleep inside the closed male flowers and forage before dawn.
Value to bees
- Nectar
- High
- Pollen
- Very high
- As a honey crop
- Not a honey source
- Which bees, and why
- In the Americas, squash bees of the genera Peponapis and Xenoglossa specialise on Cucurbita exclusively, forage before dawn when the flowers open, and males sleep inside the closed male flowers. They are frequently more effective than honey bees and are present in most North American squash fields whether anyone stocks bees or not.
Enormous open trumpet flowers with no access difficulty whatsoever — the constraint is timing, not architecture.
- Worth knowing
- A generous nectar and pollen source in the early morning, and unavailable for the rest of the day.
As a crop
- Dependence on animal pollinators
- Essential — production falls by 90% or more without animal pollinators
- In the United States
- Honey bees: pollen attractive in some conditions, nectar attractive in some conditions. Bumble bees: highly attractive. Solitary bees: Agapostemon, Melissodes, Peponapis (squash bees). Needs bee pollination: yes; managed pollinators used: yes.
- Worth knowing
- Separate male and female flowers: without a pollinator carrying pollen between them there is no fruit. Specialist squash bees (Peponapis, now treated as a subgenus of Eucera) are among its most effective visitors in the Americas.
Sources: Importance of pollinators in changing landscapes for world crops; Attractiveness of Agricultural Crops to Pollinating Bees for the Collection of Nectar and/or Pollen. Every crop compared.
Flowering
- Typically in flower
- June to September (northern hemisphere)
Individual flowers open for a single morning and close by midday, which puts a hard limit on when pollination can happen.
A typical window for the species, HoneyHQ synthesis — it moves with latitude, altitude and the year.
- When nectar flows
- Generous per flower — the blooms are very large and hold substantial nectar — but the window is only a few hours each morning.
- Year-to-year variation
- Not a honey crop in any commercial sense, because the flowers close by midday. The economic relationship is pollination, not honey.
Growing it
- Conditions
- Full sun, rich moisture-retentive soil, and a frost-free growing season. It is a hungry and thirsty crop.
- Size
- Trailing to 3 m or bushy to 1 m, depending on variety.
- Native range
- Mesoamerica, and among the earliest domesticated plants in the Americas — squash cultivation predates maize.
- Suits
- Small gardens, Large gardens, Farm scale
- Every fruit requires pollen moved from a male flower to a female one, so poor fruit set is usually a pollination problem rather than a feeding one.
- Hand-pollinate in the early morning with a paintbrush if fruit is setting badly — the flowers close by midday, so afternoon attempts fail.
- The first flush of flowers is usually all male, which alarms new growers every year and is entirely normal.
What it looks like
A sprawling annual with large rough lobed leaves and enormous bright orange-yellow trumpet flowers, the female ones sitting on a visible miniature fruit and the male ones on a plain stalk.
Sources
- Assessment Report on Pollinators, Pollination and Food Production — Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) (2016) · Systematic review Link
- The Bees of the World — Johns Hopkins University Press (2007) · Textbook
How sources are selected and weighted is set out in the sources and evidence policy.
Guides covering this plant
- Honey bees and wild beesThere are around twenty thousand bee species and only a handful make honey. Conflating the two has produced a great deal of well-meant conservation effort aimed at the one species that needs it least.
- How pollination worksPlants cannot move, so they pay something that can. Pollination is a transaction, and understanding it as one explains almost everything about flower shape.
- Which crops need pollinators, and which bees do the workCrop by crop, the need for pollinators runs from total to none. How much of that work honey bees do is a separate question, and so is whether a grower rents hives — the three answers often differ.
Tools for planning planting
- Flowering calendar
What should I plant so that something is always in flower for bees?
- Bee-friendly garden planner
What should I plant in the space I actually have?
- Plant recommendation tool
Which plant fills this specific gap?