Wild Bee Forage Plants: Optimal Supplies for Sandy Soils

Key points at a glance

• Sandy soil sites allow ground-nesting species to dig brood tunnels, but they require targeted plant selection to keep energy-intensive flight costs to a minimum.
• The proximity between the nesting site and forage plants (food sources) determines the reproductive rate of wild bee populations.
• Drought-tolerant native plants are essential to ensure a continuous supply of nectar and pollen, even during the dry month of July.

The alliance of soil structure and nutrient supply

Many wild bees, such as the Grey-backed Mining Bee (Colletes cunicularius) or various furrow bees (Lasioglossum spec.), prefer to build their nests in sandy, sparsely vegetated soil. The decisive ecological factor here is the distance to food sources. Since the females must fly back and forth between the nest and the flowers multiple times to provision a single brood cell, a high density of forage plants in the immediate vicinity (less than 50 metres) is crucial for the health of their offspring.

In July, when many classic spring bloomers have finished flowering, garden owners should strategically plant species that can cope with nutrient-poor, sandy soils while simultaneously offering high-quality sources of pollen and nectar.

Practical tips for the sandy garden

1. Structural diversity over density: Avoid a continuous carpet of plants directly at nesting sites. Ground-nesting bees need open areas of soil for take-off and landing. Use the suggested plants in small groups or islands, rather than as large flowerbeds.
2. Cascade principle: Ensure that flowering periods overlap. Viper’s Bugloss (Echium vulgare) provides an essential food source in July when other species are already going to seed.
3. Avoid soil improvement: Do not dig in compost or peat-free soil if you want to support ground-nesting species. Many wild bees rely on the physical properties of lean, sandy soils, which do not tend to become waterlogged or crusted.
4. Mowing management: Do not mow meadow areas where wild bees are nesting. If mowing is necessary, it should be done in sections so that flight paths and food supplies are not abruptly cut off.

Frequently Asked Questions

Why is sandy soil so valuable for wild bees? It is easy to dig, dries quickly after rain, and thus prevents the brood in the tunnel from becoming mouldy. It is a fundamental requirement for many specialists.

Can I rake the soil near the bees? No. Mechanical disturbance of the soil destroys fragile brood tunnels. Leave these areas untouched to protect the development of the larvae.

Which plants are best for dry conditions in July? Species like Wild Marjoram (Origanum vulgare) cope perfectly with the dry conditions of sandy soil and provide important nectar reserves for insects.

Frequently Asked Questions

Why is sandy soil so valuable for wild bees?

It is easy to dig, dries quickly after rain, and thus prevents the brood in the tunnel from becoming mouldy. It is a fundamental requirement for many species.

Can I rake the soil near the bees?

No. Mechanical disturbance of the soil destroys fragile brood tunnels. Leave these areas untouched to protect the development of the larvae.

Which plants are best for dry conditions in July?

Species like Wild Marjoram (Origanum vulgare) cope very well with dry conditions and offer important nectar reserves for wild bees.

Main article: Ground-nesting wild bees in the garden: Protecting habitats