Plants to encourage

pollenating insects

 

Help for pollinating insects (from the RHS Website)


The RHS has compiled a list of plants that will provide nectar and pollen for bees and many other types of pollinating insects.


Over the last 50 years declines have been noted in many groups of British insects, including those that visit flowers. These include some  common butterflies, moths, hoverflies and bees.

The reasons for this are various and complex but part of the problem may be the reduction in abundance of wild flowers in the countryside that has occurred over this 50 year period. Gardens are increasingly recognised as important habitats where insects can find sources of nectar and pollen.

Pollination is the process by which pollen is transferred from one flower to another, allowing flowers to become fertilised and able to produce seeds and fruits. In some plants, such as grasses and conifers, pollen is spread by the wind, but the majority of plants require insects and sometimes other animals to carry the pollen.

Apples, plums, pears, cherries, raspberries, blackberries, blackcurrants, red currants, gooseberries and strawberries all rely on insects to bring about pollination. The same is true for some vegetables, such as broad bean, runner bean and plants in the marrow-pumpkin family.

It has been estimated that the value of insect-pollinated fruits and vegetables grown in the UK is about £220 million a year. In addition there is the inestimable value of pollination provided to wild flowers and garden ornamentals, making insect pollinators a vital component of our biodiversity.

Flowers attract insects by providing them with two rich sources of food - nectar and pollen. Nectar contains sugars and provides insects with an energy source, while pollen grains contain proteins and oils.

Pollen and nectar provide the complete diet for both the adult bees and their larvae. Other insects, such as various flies and midges, beetles, wasps, thrips, bugs, butterflies and moths visit flowers to feed on pollen and nectar but may also have other dietary requirements, especially in their immature stages. Some predatory insects visit flowers to feed on other insects attracted to the blooms. All are capable of picking up pollen on their bodies and bringing about pollination when they move to other flowers of the same plant.

How to attract and support pollinating insects


Aim to have plants that are attractive to pollinating insects in flower from early spring to late autumn.


Seek plants at garden centres and nurseries having the RHS symbol pictured left.

Grow garden plants with flowers that attract pollinating insects.

Avoid plants with double or multi-petaled flowers. Such flowers may lack nectar and pollen, or insects may have difficulty in gaining access.

Never use pesticides on plants when they are in flower.

Where appropriate, British wild flowers can be an attractive addition to planting schemes and may help support a wider range of pollinating insects.

Observe the plants in your garden. If you know of plants with blooms that regularly attract insects, let the RHS know.

Encourage bees by keeping honeybees yourself or allowing a beekeeper to place hives in your garden. Nest boxes containing cardboard tubes or hollow plant stems, or holes drilled in blocks of wood will provide nest sites for some species of solitary bees. Such nests are available from garden centres or you can make your own (holes/tubes should be in a mixture of sizes with a diameter of 2-8mm).


Some pollinator insect facts

  1. Britain has 25 species of bumblebees, of which about 11 commonly           visit garden flowers.

  2. A honeybee hive can contain up to about 60,000 bees in mid summer and they can convert the nectar they collect into over 100 pounds of honey.

  3. There are about 260 species of solitary bee in Britain.

  4. There is a similar number of hoverflies, many of which have aphid predator larvae.

  5. Adult pollen beetles (Meligethes spp.) feed on pollen and are commonly seen in flowers in spring and summer.

  6. Butterflies and moths, with their long tongues (proboscis), can reach nectar in flowers that is inaccessible to short-tongued insects.

  7. Unlike humans, honeybees can see ultraviolet light and can detect patterns on petals invisible to us. The markings on the petals guide bees to the nectar-producing parts of the flower and bring the insect into close contact with the pollen-bearing structures.

  8. When foraging honeybees have located a good source of nectar or pollen, they can recruit other bees to visit the same flowers. A figure-of- eight-dance performed on the combs in the hive tells other bees how far and in which direction they need to fly to find the flowers.


Compiled by Andrew Halstead, RHS Principal Entomologist


WINTER

NOV – FEB

Clematis cirrhosa a clematis

Crocus tommasinianus a crocus

Crocus vernus a crocus

Eranthis hyemalis Winter aconite

× Fatshedera lizei

Galanthus nivalis Snowdrops - single flowered forms

Helleborus argutifolius a hellebore

Helleborus foetidus Native plant - Stinking hellebore

Helleborus × hybridus a hellebore

Helleborus × sternii a hellebore

Lonicera × purpusii a honeysuckle

Mahonia × media

Salix aegyptiaca a willow

Sarcococca hookeriana a winter box

Sarcococca hookeriana var. digyna a winter box

Sarcococca humilis a winter box

Viburnum tinus Laurustinus

SPRING

MAR–MAY

Acer campestre Native plant. Field maple

Acer platanoides Norway maple

Acer pseudoplatanus Sycamore

Acer saccharum Sugar maple

Aesculus hippocastanum Horse chestnut

Ajuga reptans Native plant. Bugle

Arabis alpina subsp, caucasica Arabis

Aubrieta deltoidea Aubrieta

Aurinia saxatilis Alyssum

Berberis darwinii

Berberis thunbergii

Buxus sempervirens Native plant Box

Caltha palustris Native plant. Marsh marigold

Cercis siliquastrum Judas tree

Chaenomeles japonica a Japanese quince

Chaenomeles speciosa a Japanese quince

Chaenomeles x superba a Japanese quince

Cheiranthus cheiri Wallflower

Cornus mas Cornelian cherry

Crataegus monogyna Native plant. Hawthorn

Crocus spp & cultivars Crocus (various)

Doronicum x excelsum Leopard’s bane

Enkianthus campanulatus

Erica carnea a heath

Erica x darleyensis a heath

Euphorbia characias a spurge

Euphorbia polychroma a spurge

Geranium phaeum Dusky cranesbill

Hebe spp & cultivars

Helleborus x hybridus a hellebore

Iberis saxatilis a candytuft

Iberis sempervirens Perennial candytuft

Ilex aquifolium Native plant. Holly

Lamium maculatum a dead nettle

Lunaria annua Honesty

Mahonia aquifolium Oregon grape

Malus baccata a crab apple

Malus domestica edible apples

Malus floribunda a crab apple

Malus hupehensis a crab apple

Malus ‘John Downie’ a crab apple

Malus sargentii a crab apple

Mespilus germanica Medlar

Muscari armeniacum Grape hyacinth

Ornithogalum umbellatum Star of Bethlehem

Pieris formosa

Pieris japonica

Primula vulgaris Native plant. Primrose

Prunus ‘Accolade’ a flowering cherry

Prunus avium Native plant. Wild and edible cherries

Prunus domestica Edible plum

Prunus dulcis Almond

Prunus incisa ‘Kojo-no-mai’ a flowering cherry

Prunus laurocerasus Cherry laurel

Prunus mume a flowering cherry

Prunus padus Native plant. Bird cherry

Prunus pendula var. ascendens ‘Rosea’ a flowering cherry

persica Peach/nectarine

Prunus spinosa Native plant. Blackthorn/sloe

Prunus tenella a flowering cherry

Prunus x yedoensis a flowering cherry

Pulmonaria angustifolia a lungwort

Pulmonaria saccharata a lungwort

Pyrus communis Pear

Ribes nigrum Blackcurrant

Ribes rubrum Red/white currant

Ribes sanguineum Flowering currant

Salix caprea Native plant. Goat Willow - male form, not female

Salix hastata ‘Wehrhahnii’ a willow

Salix lanata a willow

Skimmia japonica

Smyrnium olusatrum Alexanders

Stachyurus chinensis

Stachyurus praecox

Taraxacum officinale Native plant. Dandelion

Vaccinium cory

SUMMER

JUNE – AUG

Achillea filipendulina a yarrow

Actaea japonica a baneberry

Aesculus indica Indian horse chestnut - resistant to leaf-mining moth

Aesculus parviflora Buckeye

Agastache foeniculum

Ageratum houstonianum Floss flower

Alcea rosea Hollyhock single-flowered forms

Allium aflatunense an ornamental onion

Allium christophii an ornamental onion

Allium giganteum an ornamental onion

Allium nutans an ornamental onion

Allium schoenoprasum Chive

Amberboa moschata Sweet sultan

Anchusa azurea

Anchusa capensis

Angelica archangelica Angelica

Angelica gigas Giant angelica

Angelica sylvestris Native plant. Wild angelica

Anthemis tinctoria Golden marguerite

Antirrhinum majus Snapdragon

Aquilegia spp. Columbine

Aruncus dioicus Goatsbeard

Asparagus officinalis Vegetable asparagus

Astrantia major

Borago officinalis Borage

Buddleja davidii Butterfly bush

Buddleja globosa Orange ball tree

Calamintha nepeta subsp. Nepeta Catmint

Calendula officinalis Marigold - single-flowered forms

Callicarpa bodinieri var. giraldii Beauty berry

Callistephus chinensis Open-centred forms

Calluna vulgaris Native plant. Ling heather

Campanula carpatica a bellflower

Prunus

mbosum Blueberry

Campanula glomerata Native plant. Clustered bellflower

Campanula medium Canterbury bells

Campanula persicifolia Peach-leaved bellflower

Campsis radicans Trumpet vine

Caryopteris × clandonensis

Catalpa bignonioides Indian bean tree

Centaurea atropurpurea

Centaurea cyanus Native plant. Cornflower

Centaurea dealbata

Centaurea macrocephala

Centaurea montana

Centaurea nigra Native plant. Hard head knapweed

Centaurea scabiosa Native plant. Great knapweed

Centranthus ruber Red valerian

Centratherum intermedium Brazilian button

Cerinthe major ‘Purpurascens’ Honeywort

Cheiranthus × allionii Siberian wallflower

Clarkia elegans Single-flowered forms

Clematis vitalba Native plant. Old man’s beard/Traveller’s joy

Convolvulus tricolor Annual bindweed

Coreopsis lanceolata

Coreopsis tinctoria

Coreopsis verticillata

Cornus alba Red-barked dogwood

Cosmos bipinnatus

Cotoneaster horizontalis Herringbone cotoneaster

Cotoneaster microphyllus Small-leaved cotoneaster

Crambe cordifolia a sea kale

Crataegus monogyna Native plant. Hawthorn

Cucurbita pepo Marrow/courgette

Cuphea ignea Cigar flower

Cynara cardunculus Cardoon

Dahlia Dahlia Open centred flower forms, eg ‘Amazone’, ‘Moonfire’

Dianthus barbatus Sweet William

Dictamnus albus Burning bush

Digitalis purpurea Native plant. Foxglove

Dipsacus fullonum Native plant. Teasel

Echinacea purpurea Coneflower

Echinops bannaticus a globe thistle

Echinops ritro a globe thistle

Echinops setifer a globe thistle

Echium vulgare Native plant. Viper’s bugloss

Elaeagnus angustifolia Oleaster

Erica cinerea Native plant. Bell heather

Erica erigena a heath

Erica vagans Native plant. Cornish heath

Erigeron spp. and hybrids Fleabane

Eryngium × tripartitum a sea holly

Eryngium alpinum a sea holly

Eryngium giganteum a sea holly/ Miss Willmott’s ghost

Eryngium planum a sea holly

Escallonia cultivars

Eschscholzia californica Californian poppy

Eupatorium cannabinum Native plant. Hemp agrimony

Eupatorium maculatum

Ferula communis Giant fennel

Foeniculum vulgare Fennel

Fragaria × ananassa Strawberry

Fuchsia magellanica a hardy fuchsia

Gaillardia × grandiflora Blanket flower

Geranium pratense Native plant. Meadow cranesbill

Geranium ROZANNE =’ Gerwat’ a hardy geranium

Geum ‘Borisii’ a geum

Gilia capitata Queen Anne’s thimbles

Hebe spp. and cultivars

Helenium ‘Moerheim Beauty’

Helenium ‘Sahin’s Early Flowerer’

Helenium ‘Sonnenwunder’

Helianthus annuus Sunflower Single-flowered forms; avoid pollen-free cultivars.

Heliotropium arborescens Cherry pie/ Heliotrope

Heracleum sphondylium Native plant. Hogweed

Hesperis matronalis Sweet rocket/ Dame’s violet

Hydrangea anomala subsp. petiolaris Climbing hydrangea

Hydrangea paniculata Cultivars with many fertile flowers eg ‘Kyushu’, ‘Big Ben’, ‘Floribunda’, ‘Brussels Lace’

Hyssopus officinalis Hyssop

Iberis amara Candytuft

Ilex aquifolium Native plant. Holly

Inula ensifolia

Inula hookeri

Inula magnifica

Jasminum officinale Common jasmine

Kalmia latifolia Calico bush

Knautia arvensis Native plant. Field scabious

Knautia macedonica

Koelreuteria paniculata Golden-rain tree

Laurus nobilis Bay tree

Lavandula × intermedia a lavender

Lavatera olbia a shrubby mallow

Lavatera trimestris

Leucanthemum × superbum Open-centred flower forms

Leucanthemum vulgare Native plant. Ox-eye daisy

Ligustrum ovalifolium a privet

Ligustrum sinense a privet

Limnanthes douglasii Poached egg plant

Limonium latifolium a sea lavender

Linaria purpurea Purple toadflax

Lobularia maritima Sweet alyssum

Lonicera periclymenum Native plant. Common honeysuckle

Lychnis coronaria Rose campion

Lychnis flos-cuculi Native plant. Ragged robin

Lysimachia salicaria Native plant. Purple loosestrife

Lysimachia vulgaris Native plant. Yellow loosestrife

Lythrum virgatum ‘Dropmore Purple’ a loosestrife

Malope trifida Annual mallow

Malva moschata Native plant. Musk mallow

Matthiola incana Stock

Mentha aquatica Native plant. Water mint

Mentha spicata Garden mint

Monarda didyma Bergamot

Myosotis spp Forget-me-not

Nemophila menziesii Baby blue-eyes

Nepeta × faassenii a catmint

Nicotiana alata a tobacco

Nigella damascena Love-in-a-mist

Oenothera biennis Evening primrose

Olearia x haastii Daisy bush

Onopordum acanthium Giant thistle

Origanum ‘Rosenkuppel’ Majoram

Origanum vulgare Native plant. Majoram

Papaver orientale Oriental poppy

Papaver rhoeas Native plant. Field poppy

Parthenocissus quinquefolia Virginia creeper

Parthenocissus tricuspidata Boston ivy

Penstemon cultivars

Perovskia atriplicifolia

Persicaria amplexicaulis a bistort

Persicaria bistorta Native plant. a bistort

Phacelia tanacetifolia

Phaseolus coccineus Runner bean

Polemonium caeruleum Native plant. Jacob’s ladder

Potentilla fruticosa Native plant. a shrubby potentilla

Potentilla ‘Gibson’s Scarlett’

Ptelea trifoliata Hop tree

Pyracantha coccinea Firethorn

Reseda odorata Mignonette

Robinia pseudoacacia Black locust/False acacia

Rosa canina Native plant. Dog rose

Rosa rubiginosa Native plant. Sweet briar rose

Rosa rugosa Hedgehog rose

Rosmarinus officinalis Rosemary

Rubus fruticosus Native plant and edible blackberry

Rubus idaeus Raspberry

Rudbeckia fulgida

Rudbeckia hirta

Rudbeckia laciniata Open-centred flower forms

Salvia horminum Annual clary

Salvia nemorosa a sage

Salvia officinalis Common sage

Scabiosa caucasica Scabious

Scabiosa columbaria Native plant. Small scabious

Sedum spectabile Ice plant

Sedum telephium Native plant. Orpine

Sidalcea malviflora Checkerbloom

Solidago spp. and cultivars Golden rod

Sorbus aria Native plant. Whitebeam

Sorbus aucuparia Native plant. Mountain ash/rowan

Spiraea japonica

Stachys byzantina Lambs’ ears

Stachys macrantha

Symphoricarpos albus Snowberry

Tagetes patula French marigold

Tamarix ramosissima Tamarisk

Tanacetum vulgare Native plant. Tansy

Telekia speciosa

Tetradium daniellii

Teucrium chamaedrys

Thymus serpyllum and cultivars Native plant. Wild thyme

Thymus spp. and cultivars Thyme

Tilia × europaea Common lime

Tilia cordata Native plant. Small-leaved lime

Tilia maximowicziana a lime tree

Tilia oliveri a lime tree

Tilia platyphyllos Large-leaved lime

Tilia tomentosa a lime tree

Tithonia rotundifolia Mexican sunflower

Verbascum olympicum a mullein

Verbascum thapsus Native Plant. Common mullein

Verbena × hybrida

Verbena bonariensis

Verbena rigida

Veronica longifolia

Veronicastrum virginicum

Viburnum lantana Native plant. Wayfaring tree

Viburnum opulus Native plant. Guelder rose

Vicia faba Broad bean

Weigela florida

Zauschneria californica Californian fuchsia

Zinnia elegans

AUTUMN

SEPT – OCT

Aconitum carmichaeli a monkshood

Actaea simplex Bugbane

Anemone hupehensis a japanese anemone

Anemone x hybrida a japanese anemone

Arbutus unedo Strawberry tree

Aster amellus a perennial aster

Aster ericoides f. prostratus a perennial aster

Aster koraiensis a perennial aster

Aster lateriflorus var horizontalis a perennial aster

Aster novae-angliae a Michaelmas daisy

Aster novi-belgii a Michaelmas daisy

Aster oolentangiensis a perennial aster

Aster turbinellus a perennial aster

Aster × frikartii ‘Mönch’ a perennial aster

Campanula poscharskyana a bellflower

Ceratostigma plumbaginoides

Clematis heracleifolia a clematis

Colchicum spp. Autumn crocus

Dahlia cultivars Dahlia - single-flowered forms

Elaeagnus pungens

Elaeagnus × ebbingei

Fatsia japonica Japanese aralia

Hedera colchica Persian ivy

Hedera helix Native plant. Ivy

Hedera helix ‘Arborescens’

Helianthus × laetiflorus a sunflower

Leucanthemella serotina

Salvia leucantha Mexican bush

Salvia ‘Mystic Spires Blue’

Tilia henryana a lime tree - one of the last to flower