Although my emphasis this year has been on suggesting native plants for bumblebees, sometimes cultivars can help fill in the bloom gaps. Here's a list of some cultivars that can be used in perennial borders for bees, especially those species such as bumblebees that have a long flight season, but are unable to store food for long periods of time the way honeybees can.
Victory Gardens for Bees: (Check the Perennial Chapter for more suggestions.)
White Oriental Poppy (Papaver orientale ‘Royal Wedding’)
Asclepias incarnata ‘Ice Ballet’
Physostegia virginiana ‘Crystal Peak White’
Shrubby Penstemon (Penstemon fruticosus ‘Purple Haze’)
Aster x frikartii ‘Monch’
Persicaria amplexicaulis ‘Firetail’
Dahlia ‘Bishop of Llandoff’
Scented Cultivars Recommended by Great Plant Picks
Rosa “Golden wings”, a yellow, repeat blooming rose.
Golden Bluebeard (Caryopteris incana ‘Jason’) blue (woodsy scent). Golden-leaved cultivar.
Cutleaf Russian Sage (Perovskia ‘Filigran’)
Hybrid Hyssop (Agastache ‘Blue Fortune’)
Rhododendron ‘Snowbird’ a deciduous Azealea
Anenome Clematis (Clematis montana var rubens ‘Tetrarose’)
Mock Orange (Philadelphis ‘Belle Etoile’)
Hybrid Mahonia (Berberis x media ‘Charity’)
Other Bee Cultivars Recommended by Great Plant Picks
Strawberry Tree (Arbutus unedo) for birds and bees
Spreading Willowleaf Cotoneaster (Cotoneaster salicifolius ‘Repens’)
Golden-leaved Salmonberry (Rubus spectabilis ‘Golden Ruby’)
Korean Mountain Ash (Sorbus alnifolia )
Blueberry (Vaccinium ‘Sunshine Blue’)
False Indigo (Baptisia ‘Purple Smoke’)
Threadleaf Coreopsis (Coreopsis verticillata ‘Zagreb’)
Persian Catmint (Nepeta racemosa ‘Walker’s Low’)
Hybrid Rhododendron (Rhododendron ‘Blue Boy’)
Repeat-blooming shrub rose (Rosa SWEET JULIET)
Japanese snowball (Styrax japonicus SNOWBALL)
Species Tulip (Tulipa saxatilis ‘Lilac Wonder’)
California Lilac (Ceanothis ‘Victoria’)
Purple Coneflower (Echinacea purpurea ‘Bravado’)
Joe Pye Weed (Eupatorium maculatum ‘Gateway’)
Black-Eyed Susan (Rudbeckia fulgida var. sulvantii ‘Goldsturm’)
Goldenrod (Solidago rugosa ‘Fireworks’)
More Perennial Cultivars for Bees
(Ones with dates were perennials of the year)
2008 Cranesbill Geranium: Geranium 'Rozanne'
2007 Catmint (Nepeta racemosa 'Walker's Low') Must be divided, seeds are sterile
Faassen’s Catmint Nepeta x faassenii ‘Dropmore’
2000 Scabiosa columbaria 'Butterfly Blue'
Rudbeckia fulgida or R. hirta bloom for a long time, but only seem to attract bees for a short time while producing pollen. Try a Rudbeckia laciniata cultivar.
1998 Echinacea purpurea 'Magnus', (also try ‘White Swan’)
1997 Salvia 'Mainacht' (May Night)
Salvia farinacea ‘Victoria’
Salvia vertilicillata ‘Purple Rain’
1996 Penstemon digitalis 'Husker Red'
1995 Perovskia atriplicifolia
1992 Coreopsis verticillata 'Moonbeam' (There’s also a ‘Sunbeam’)
Pulmonaria ‘Trevi Fountain’: Resistant to rust and powdery mildew
Anise Hyssop ‘Blue Boa’
Veronica ‘Giles Van Hees’: They are usually purple. This is a dwarf pink form with a long bloom time.
Clematis macropetala —early blooming and a hit with bumblebees
Beard Tongue Penstemon ‘Evelyn’: The bumblebees crawl right inside.
Helianthus annuus ‘Lemon Queen’ (I like Earthwalker because it has multiple heads.)
Bluebeard (Caryopteris x clandonensis)
Christmas Rose (Helleborus x Ballardiae 'HGC Pink Frost')
Heath (Erica x Darleyensis ‘Kramer Rote’)
Dragonhead (Dracocephalum argunense ‘Fuji Blue’) A short cultivar, suitable for borders
Earthwise Suggestions: check the link for more
‘Orange Spice’ thyme Thymus spp
Rosa ‘Frau Dagmar Hartopf’
California Lilac (Ceanothus ‘Victoria’)
Pincushion Flower (Scabiosa columbaria ‘Moon Dance’)
‘Autumn Joy’ Sedum var.
I have been asked to explain what I mean when I say “avoid doubles” when choosing cultivars for bees. These Teddy Bear sunflowers are a good example of mutant flowers that provide very few food rewards for bees. I found a good article explaining what’s going on with these sunflowers, the ones that are made famous by Van Gogh. Of course he was painting in the late 1800’s before the Teddy Bear was invented, so they would have been called something else, in Dutch of course.
Information on how to avoid neonicatinoids:
A good Xerces Guide on basic bee identification tips: