Native or Exotic? Double or Single? Evaluating Plants for Pollinator-friendly Gardens.

Area of Science:

• Botany
• Ecology
• Entomology

Background:

• Pollinator health is crucial for ecosystem function and agriculture.
• Understanding nectar availability and accessibility is key to supporting pollinator populations.
• Plant breeding can impact nectar production and pollinator interactions.

Purpose of the Study:

• To assess nectar rewards in native and non-native plant species.
• To investigate the influence of flower morphology (single vs. double) on nectar accessibility.
• To evaluate the suitability of various plant species for supporting British pollinator communities.

Main Methods:

• Dawn-to-dusk monitoring of insect visits to flowers.
• Measurement of nectar secretion rates and standing nectar crops.
• Comparison of nectar characteristics in single and double flower variants.

Main Results:

• British native species like Salvia pratensis and Stachys palustris are nectar-rich with accessible nectar for local bees.
• Exotic species (e.g., Salvia splendens) often possess deep corollas, hindering native bee access.
• Double-flowered variants, except for Calendula officinalis, generally produced less nectar and were less visited by insects.

Conclusions:

• Native British wildflowers provide valuable nectar resources for indigenous pollinators.
• Flower depth and pollinator co-evolution significantly influence nectar exploitation.
• Plant modifications, such as double flowers, can negatively impact nectar availability and pollinator attraction.