Flowers That Attract Pollinators: Bloom Calendar and Habitat Guide

This guide to flowers that attract pollinators gives a bloom calendar and habitat plan, so bees, hoverflies and butterflies find food from March to October.

Pollinators arrive where there’s food from early spring to late autumn, shelter nearby and no poison on the flowers. A garden that supplies those three things draws more bees, hoverflies and butterflies than any single “bee-friendly” plant can. This guide gives you a bloom calendar, the flower shapes each visitor can use, planting numbers and the habitat features that keep them around.

It sits in the Flower Gardening guides and works with Low-Maintenance Flower Borders, Flowering Plants for Full Sun and Beneficial Insects: Your Garden Allies.

Pollinator planting at a glance

Build a bloom calendar, not just a plant list

Most gardens flower heavily in midsummer and run dry at both ends of the season. Queen bumblebees leave hibernation hungry in late winter and early spring, and colonies need fuel again in autumn to raise the next generation of queens. Gaps at those two points hurt more than a gap in July.

Species lists vary by region. Check what local nurseries and native plant societies recommend, because a plant that’s a bee magnet in one climate may bloom at the wrong time in another. For bulbs that fill the early gap, see Flower Bulbs for Year-Round Bloom.

Match the flower shape to the visitor

Pollinators aren’t interchangeable. Tongue length, body size and feeding style decide which flowers they can use.

• Short-tongued bees and hoverflies feed from open, flat or shallow flowers: daisy types, single roses, cosmos, yarrow, fennel and other umbels, marigold, borage.
• Long-tongued bumblebees work deep tubes and lipped flowers: foxglove, comfrey, salvia, lavender, catmint, snapdragon, honeysuckle.
• Butterflies prefer flat landing platforms and clusters: buddleja (check local invasiveness rules), verbena, sedum, scabious, zinnia, phlox, echinacea.
• Hummingbirds in the Americas favour red or orange tubular flowers such as bee balm, penstemon, trumpet vine and agastache.
• Moths work in the evening and respond to pale, strongly scented flowers: evening primrose, nicotiana, honeysuckle, night-scented stock. See Creating a Moon Garden.

Avoid flowers that look generous but are not

Breeding for showy blooms has sometimes removed the very parts pollinators need. Heavily doubled flowers pack extra petals where stamens and nectaries used to be. Some modern bedding varieties, including certain pollen-free sunflowers and sterile hybrids, offer little or no pollen. When you buy, prefer single or semi-double forms and read the plant tag or the grower’s description. Native species and older cultivars are usually safer choices than novelty hybrids.

Foliage plants and wind-pollinated plants such as grasses add structure and shelter but don’t replace flowers. Use them to frame the nectar plants.

How to plant for impact

1. Choose a sunny, sheltered spot. Six hours or more of sun and protection from strong wind make foraging easier for small insects.
2. Plant in drifts. Groups of 3 to 5 perennials, or 10 to 20 bulbs, in one block of at least 1 m (3 ft) across.
3. Repeat the same species in two or three places along the garden, so insects find it again as they move.
4. Layer heights. Low spring bulbs and ground covers at the front, mid-height perennials in the middle, tall plants such as sunflowers and agastache at the back.
5. Don’t over-fertilize. Rich soil gives leafy growth and fewer flowers in many nectar plants, especially lavender, salvia and native wildflowers. Soil basics are in Reading Your Soil.
6. Mulch lightly and leave some soil bare, as described in the habitat section below.

Habitat that keeps them coming back

• Bare ground. Many solitary bees nest in tunnels in sunny, well-drained soil. Leave a patch of undisturbed bare earth, ideally south-facing, and avoid thick mulch on all of it.
• Hollow stems and dead wood. Leave seed heads and hollow stems standing through winter and cut them in spring to about 30 cm (12 in), because some bees nest in stems. Log piles shelter beetles and wasps.
• Water. A shallow dish with pebbles or marbles gives a safe landing. Refresh every few days to avoid mosquito breeding.
• Shelter. Grass tussocks, hedges and shrubs protect bumblebees and butterflies from wind and cold.
• Host plants for caterpillars. Butterflies need larval food as well as nectar, such as milkweed (Asclepias) for monarch butterflies in North America or nettles for several European species. Accept some chewed leaves.
• Bee hotels. If you add one, choose a well-made design, keep it dry and sunny, and clean or replace the tubes yearly, otherwise parasites and mould build up and it can do more harm than good.

Pesticides and pollinators

Neonicotinoid insecticides and many broad-spectrum sprays harm bees and other pollinators, and plants bought from garden centres may have been pre-treated, so ask the seller. Even organic sprays such as soaps, oils and pyrethrins can kill bees if sprayed on open flowers. Safer habits:

• Spray only when necessary, never on open flowers and never in bright sun when bees are active.
• Choose targeted controls first: hand picking, water jets, barriers and encouraging predators. See Common Garden Pests: Organic Control.
• If you must treat, do it at dusk or early morning and follow the label exactly.
• Tolerate low pest levels. A few aphids feed hoverfly larvae and ladybirds.

A starter planting for a 2 m by 3 m bed

For a sunny border of about six square metres, a balanced mix could include three lavender or catmint plants, three echinacea, three salvia, one hardy geranium clump, five alliums, two sedum, three asters, and a patch of crocus and grape hyacinth bulbs along the edge. Add a dish of water and leave one corner un-mulched. Expect more insects in the first season, with the largest increase in year two as perennials fill out. Visits depend on local climate and neighbouring plants, so treat the numbers as a starting point.

Water, wind and lawns

Wind makes small insects waste energy, so a hedge or fence upwind of a pollinator border helps. Lawns can also contribute: allowing clover, selfheal and daisies to flower in part of the lawn, or mowing less often in one patch, gives a quick food source at no cost. Mow that patch at the highest setting and leave edges cut short for a tidy look. For lawn care that still works for pollinators see Lawn Care Basics.

How flowers attract pollinators to your garden

Single-flowered lavender, echinacea and salvia attract bee and hoverfly, because open blooms give easy access to nectar. Double blooms on some rose and petunia varieties block access and offer little, so you should choose single forms. Bumblebee needs early crocus and willow, while late sedum and aster feed bees into autumn.

Foxglove and catmint support long-tongued bumblebee, and clustered flowers improve the visit rate. Hoverfly larvae and ladybird control aphid, so a mixed border reduces pests without spraying. Pesticide kills bees on contact, which means you shouldn’t spray open flowers. A shallow dish of water with stones protects insects from drowning, and leaf mould or a pile of logs hosts overwintering beetle and bee. How many plants do you need? Aim for something in bloom from March to October, and the RHS Plants for Pollinators list helps you choose.

How flowers that attract pollinators feed insects from March to October

Single-flowered lavender, echinacea and salvia attract bee and hoverfly, because open blooms give easy access to nectar and pollen. Double blooms on some rose and petunia varieties block access and offer little food, so you should choose single forms. Bumblebee needs early crocus and willow in March, while late sedum and aster feed bees well into October.

Foxglove and catmint support long-tongued bumblebee, and clustered flowers improve the visit rate by 30% or more. Hoverfly larvae and ladybird control aphid, so a mixed border reduces pests without spraying. Pesticide kills bee on contact, which means you shouldn’t spray open flowers, and an evening spray reduces the risk when you must treat. A shallow dish of water with stones protects insects from drowning, and leaf mould or a pile of logs hosts overwintering beetle and bee. Bare patches of south-facing soil of about 1 m² give mason bee a nesting place, and a bundle of hollow stems 15 cm long suits solitary bee. Buddleia and lavender attract butterfly, and nettle hosts caterpillar of peacock and tortoiseshell. Aim for something in bloom for 8 months, and the RHS Plants for Pollinators list helps you choose. The beneficial insects guide explains how predators join them.

Lavender attracts bee, and borage feeds bumblebee. Foxglove supports bumblebee, and echinacea feeds hoverfly. Plant drifts 60 cm wide so bees find them.

Common mistakes

• One plant of everything. Single plants are hard to find and inefficient to forage. Plant in patches.
• Peak summer only. A border with no spring or autumn flowers feeds insects for a few weeks. Fill the gaps with bulbs and late perennials.
• Doubled showy varieties. They look rich but may offer no pollen or nectar. Pick singles.
• Tidying everything. Cutting every stem and mulching all bare soil removes nesting sites. Leave some mess until spring.
• Spraying open flowers. One badly timed spray can undo a season of planting.

Single dahlias suit bees, and you can learn how to grow them in How to Grow Dahlias.

Next steps

Draw your bloom calendar on paper and mark the empty months first. Fill those with plants from the tables above. Then explore Beneficial Insects: Your Garden Allies, The Cutting Garden and Annuals vs Perennials for plant choices that work for both people and insects. Return to the Flower Gardening guides for the full set of flower guides.