Upper Thames Branch Gardening for Butterflies

  • Gardens

  • Many of us try to attract butterflies by planting nectar sources, like buddleia, in our gardens. Planting flowers raises an expectation which often leads to the question, “Why don’t I see many butterflies?”.
     
    There are several reasons, but the most important is that nectar sources simply retain butterflies which would otherwise fly straight through your garden. Nectar sources alone do not increase the numbers of butterflies.
     
    Unlike bees that really benefit from extra nectar sources (as all the stages of their life cycle feed on nectar), butterflies only use nectar in the adult stage. Every adult butterfly spent weeks feeding as a caterpillar. Unless the plants that caterpillars need are growing near (or better, in) your garden you will not see the adults.

    Peacock butterfly on blackthorn flowers, which provide an excellent nectar supply early in the year. The leaves are the foodplant of several species of garden moth.
    A solution that is proven to work is to grow the plants that caterpillars eat and which also have attractive flowers to retain the adults when they emerge. Seeing butterflies that you know bred and fed as caterpillars in your garden, gives a real sense of achievement, just as seeing young birds from a nest in your garden.
     
    It is even possible to grow plants that serve the dual purpose of feeding the caterpillars, with their leaves, and the adults with their flowers.
     
    Here are some planting suggestions for various areas of the garden.
    Six-spot Burnet moth caterpillar, which feeds on Birds-foot Trefoil
    Don't forget to send your garden records to the Garden recording co-ordinator. There is a new spreadsheet which you can download for this purpose. If you prefer to send in records on paper, the old-style form is available as a PDF. Garden records can also be submitted to BC's Garden Butterfly Survey website

    Plants for long grass areas (un-mown)
    Almost every garden has a patch of grass that could feed up to nine species of our commoner local butterfly caterpillars and maybe 40 moth species’ caterpillars.
     
    The most useful thing is to leave a strip of grass uncut until October. This works best if the strip is wider than 75cm/2.5 ft, in the sun and alongside a hedge or fence (to act as a wind break). There are various plants to grow in both the longer uncut grass and the shorter mown parts of the lawn. A really helpful plant to put in the long grass strip is Yellow Rattle (Rhinanthus minor). Although no butterfly caterpillars eat its leaves (Grass Rivulet moth caterpillars do) bumble bees love the flowers and, more crucially, it parasitises the grass around it, making the turf less dense, which assists other plants to thrive. Yellow Rattle will not grow out into a lawn, as mowing destroys it. Several of the other plants suggested are invasive and removing their flower heads before the seeds are cast will help control their spread around the garden.
     
    Nectar sources and caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Cuckoo-flower
    (Cardamine pratensis)
    • Orange-tip
    • Green-veined White
      Spring
    Jack-in-the-Hedge or Hedge Garlic
    (Alliaria petiolata)
    • Orange-tip
    • Green-veined White
    Small White
    Large White
    Spring
    Marjoram
    (Origanum majorana)
    • Mint moth • Burnished Brass Summer
    Ragwort
    (Jacobaea vulgaris)
    • Cinnabar   Summer
    Thistles
    (Cirsium, Carduus spp.)
    • Painted Lady
    • Frosted Orange
    • Burnished Brass
      Summer
    Willowherbs
    (Epilobium spp.)
    • Elephant Hawkmoth
    • Setaceous Hebrew Character
    • Small Elephant Hawkmoth
    • Bright-line Brown-eye
    Summer (poor nectar source)
    Caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Bedstraw
    (Galium spp.)
    • Common Carpet
    • Hummingbird Hawkmoth
    • Red Twin-spot Carpet
    • Elephant Hawkmoth
    • Small Elephant Hawkmoth
    • Flame Shoulder
     
    Bents grasses
    (Agrostis spp.)
    • Meadow Brown • Gatekeeper  
    Cocksfoot grass
    (Dactylis glomerata)
    • Essex Skipper
    • Large Skipper
    • Meadow Brown
    • Ringlet
    • Drinker
    • Clouded Bordered Brindle
    • Dark Arches
    • Small Skipper
    • Marbled White
    • Speckled Wood
    • Common Wainscot
    • Bright-line Brown-eye
     
    Couch grass
    (Elytrigia repens)
    • Ringlet
    • Speckled Wood
    • Dark Arches
    • Rustic Shoulder Knot
    • Essex Skipper
    • Gatekeeper
    • Marbled Minor
    • Bright-line Brown-eye
     
    Docks and Sorrels
    (Rumex spp)
    • Small Copper
    • Blood-vein
    • Ruby Tiger
    • White Ermine
    • Angle Shades
    • Rustic
    • Shuttle-shaped Dart
     
    False Brome grass
    (Brachypodium sylvaticum)
    • Meadow Brown
    • Speckled Wood
    • Gatekeeper
    • Straw Dot
    • Essex Skipper
    • Large Skipper
    • Small Skipper
     
    Fescue grass
    (Festuca spp)
    • Meadow Brown • Marbled White  
    Meadow grasses
    (Poa spp)
    • Meadow Brown
    • Gatekeeper
    • Ringlet
       
    Stinging Nettle
    (Urtica dioica)
    • Comma
    • Red Admiral
    • Peacock
    • Small Tortoiseshell
    • Setaceous Hebrew Character
    • Garden Tiger
    • Mother of Pearl
    • Nettle–tap
    • Small Magpie Moth
    • Snout
    • Burnished Brass
    • Painted Lady
    • Angle Shades
    • White Ermine
    • Flame
    • Silver Y
    • Spectacle
     
    Yorkshire Fog grass
    (Holcus lanatus)
    • Marbled White
    • Small Skipper
    • Speckled Wood
       
    Nectar sources Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Greater Knapweed
    (Centaurea scabiosa)
        Summer
    Field Scabious
    (Knautia arvensis)
        Summer

    Plants for short grass areas (un-mown)
    Mowing in spring to reduce grass length is helpful but after May it is best not to mow until September. Cutting meter-wide paths through the grass area will increase butterfly and moth numbers more successfully than having all short, or all long, grass areas. You should always have some longer grass to act as shelter for the adult butterflies and moths. Well drained areas will host more caterpillars than damp ones.
     
    Nectar sources and caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Birds-foot Trefoil
    (Lotus corniculatus)
    • Common Blue
    • Six-spot Burnet
    • Dingy Skipper
    • Burnet Companion
    • Mother Shipton
    Summer
    Dandelion
    (Taraxacum officinale)
    • Ruby Tiger • Dark Chestnut
    • Orange Swift
    Spring/Summer
    Red Clover
    (Trifolium pratense)
    • Silver Y • Burnet Companion
    • Mother Shipton
    Summer
    Thyme
    (Thymus spp)
    • Mint moth • Crimson and Gold moth Summer
    Caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Ribwort Plantain
    (Plantago lanceolota)
    • Ruby Tiger
    • Heart and Dart
    • Flame Shoulder
    • Rustic
     
    Sheep’s Sorrel
    (Rumex acetosella)
    • Blood-vein • Small Copper  
    Nectar sources Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Lesser Celandine
    (Ranunculus ficaria)
        Spring

    Plants for borders and containers
    In addition to the plants listed for use in long and short grass areas, there are plants which will do well in borders and in pots, but struggle in a grassed area. It is worth considering the amount of sun they will get before positioning them; and how you will group the plants. A group of similar plants will be more likely to attract egg laying females than individual plants spread around the garden.
     
    Many caterpillars will thrive in a semi shaded spot but some will need to be in full sun, or full shade. Pots not only allow the growing of plants in spaces with no soil, or with a different pH to the local soil, but also the movement of the plant during the year, including bringing them under cover for the winter. Plants with very invasive roots (e.g. nettles) can be restrained inside pots.
     
    Nectar sources and caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Buddleia ‘buzz’ and ‘chip’ (dwarf varieties) • Mullein moth   Summer
    Canadian Goldenrod
    (Solidago canadensis)
    • Common Wainscot   Autumn
    Foxglove
    (Digitalis purpurea)
    • Lesser Yellow Underwing   Summer
    Honesty
    (Lunaria rediviva)
    • Orange-tip
    • Green-veined White
      Spring
    Larkspur
    (Delphinium spp)
    • Golden Plusia   Summer
    Lily of the Valley
    (Convallaria majalis)
    • Common Swift   Spring (poor nectar source)
    Lucerne
    (Medicago sativa )
      • Burnet Companion
    • Mother Shipton
    Summer/Autumn
    Meadowsweet
    (Filipendula ulmaria )
    • Hebrew Character   Summer (poor nectar source)
    Nasturtium
    (Tropaeolum spp)
    • Large White • Small White
    • Green-veined White
    Summer (poor nectar source)
    Mullein
    (Verbascum spp)
    • Mullein moth   Summer
    Red Valerian
    (Centranthus ruber)
    • Angle Shades   Spring/Summer/Autumn
    Winter flowering heathers
    (Calluna vulgaris)
    • Common Plume
    • Emperor moth
    • Beautiful Brocade
    • Ingrailed Clay
    • Glaucous Shears
    Autumn/Winter
    Caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Stinging Nettle
    (Urtica dioica)
    (This plant is most useful when young. Cutting back in late June to encourage new growth will greatly increase its usage. Best not to cut all plants at the same time)
    • Comma
    • Red Admiral
    • Peacock
    • Small Tortoiseshell
    • Setaceous Hebrew Character
    • Garden Tiger
    • Mother of Pearl
    • Nettle–tap
    • Small Magpie Moth
    • Snout
    • Burnished Brass
    • Painted Lady
    • Angle Shades
    • White Ermine
    • Flame
    • Silver Y
    • Spectacle
     
    Tufted Hair Grass
    (Deschampsia caesiptosa (ornamental grass Goldtau)
    • Ringlet
    • Dark Arches
    • Common Rustic
    • Clouded Brindle
     
    Nectar sources Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Aster
    (Asteraceae cultivars)
        Autumn
    Aubretia
    (Aubrieta cultivars)
        Spring
    Grape Hyacinth
    (Muscari cultivars)
        Spring
    Hemp Agrimony
    (Eupatorium cannabinum)
        Summer
    Ice Plant
    (Sedum spectabile)
        Autumn
    Lavender
    (Lavandula spp)
        Summer/Autumn
    Verbena
    (Verbena bonariensis)
        Summer/Autumn

    Plants for hedges and woodland edges
    Hedges and, in some gardens, woodland edges, are very helpful to butterflies and especially moths. They can provide foodplants and give shelter from intense sun, wind and rain and in winter, frosts. They provide places for the caterpillars, pupae and adults to hide away from predators and parasites. The tallest plants in the hedge, or stems protruding from it, may well act as sites where adults can congregate to find mates and, of course, many of the hedge plants, on whose leaves caterpillars feed, also have flowers with nectar; and can produce fruits and nuts for a range of wildlife.
     
    The best hedges are 3m tall and at least as wide. They are not trimmed to produce a vertical edge, but have small bays and promontories as various species in the hedge grow at different rates. The benefit of the hedge will be increased if a 0.7 metre wide strip of uncut grass borders its base.
     
    Nectar sources and caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Apple
    (Malus spp)
    • Winter moth   Spring (poor nectar source)
    Blackthorn
    (Prunus spinosa)
    • November moth
    • Pale Brindled Beauty
    • Brown-tail
    • Yellow-tail
    • Emperor moth
    • Early Thorn
    • Dark Chestnut
    • Grey Dagger
    Spring
    Bramble
    (Rubus fructiosus)
    • Mottled Beauty
    • Peppered Moth
    • Emperor moth
    • Angle Shades
    • Brown-tail
    Summer
    Honeysuckle
    (Lonicera) spp
    • Yellow-tail • Early Thorn
    • Buff Ermine
    Summer
    Ivy
    (Hedera helix)
    • Holly Blue
    • Swallow-tail moth
    • Willow Beauty Autumn
    Privet
    (Hedera helix)
    • Privet Hawk-moth • Engrailed Summer
    Sallow
    ( spp)
    • Eyed Hawk-moth
    • Pale Prominent
    • Early Thorn Spring
    Caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)  
    Buckthorn
    (Rhamnus cathartica & Frangula alnus)
    • Brimstone
    • Mottled Beauty
    • Pale Brindled Beauty
    • Emperor moth
     
    Hazel
    (Corylus avellana)
    • Brimstone
    • Mottled Beauty
    • Pale Brindled Beauty
    • Emperor moth
     

    Large Trees
    If you have the space (and you will need plenty!) various large tree species will provide food for as many moth caterpillars as the plants listed in the other sections. Trees have been shown to bring more wildlife to an area than any other single feature, even ponds.
     
    It is not a good idea to plant a tree species capable of growing to 5 m near domestic buildings and trying to restrict its growth with occasional pollarding. The roots can do extensive damage to pipes and foundations. However, there are places where larger trees are suitable and very productive. As with smaller plants, it is more useful to have a group of the same species than have a single tree. So, take account of those in adjacent land - within fifty metres but outside the garden.
     
    Caterpillar food plants Frequently used as food plant by Occasionally used as food plant by Season (if nectar source)
    Ash
    (Fraxinus excelsior)
    • November moth
    • Mottled Beauty
    • Privet Hawk-moth Summer (aphid honey-dew)
    Aspen
    (Populus tremula)
    • November moth
    • Mottled Beauty
    • Privet Hawk-moth  
    Elm
    (Ulmus spp)
    • Comma
    • Lime Hawk-moth
    • White-letter Hairstreak  
    Oak
    (Quercus robur & Q. petreae)
    • Purple Hairstreak
    • Angle Shades
    • Dark Chestnut
    • Mottled Beauty
    • Oak Hook-tip
    • Yellow-tail
    • Pale Tussock
    • Vapourer moth
    • Buff–tip
    Summer (aphid honey-dew)
    Silver Birch
    (Fraxinus excelsior)
    • Vapourer moth
    • Peppered Moth
    • Common Quaker
    • Mottled Beauty
    • Angle Shades
    • Lime Hawk-moth
    • Pale Tussock
    • Yellow-tail
    • Buff–tip
    • Lesser Swallow Prominent