I started to make a list of some garden plants that bees use and a few of the many wild flowers or flowering “weeds”:
Grape Hyacinths, Crocuses, Scabious, Wallflowers (especially Erysimum Bowles's Mauve), Sea-pink and Asters; also Allium, Hardy or Cranesbill Geraniums, Echinacea (Coneflowers) and Rudbeckias, the Heleniums {(sneezeweed) especially Helenium Autumnale & Helenium 'Sahin's Early Flowerer'}, Calamint, Borage, Veronicastrum virginicum, Sedum spectabile, Hyssop, Veronica spicata (Spiked Speedwell), Teucrium hircanicum (Wood Sage), Echium blue bedder (Viper's Bugloss), Campanula (Bellflowers), Lavendula (Lavender), Erygium giganteum (Sea Holly or 'Miss Willmott's' ghost). Himalayan balsam, Rosebay Willow Herb (Fireweed), Dandelions, Teasels, Thistles. Persicaria amplexicaulis also known as Knotweed: fire tail. and in the Self seeding 'bee' plants list
Alyssum (Lobularia maritima): Borage (Borago officinalis): Buckwheat (Fagopyrum esculentum): Calendula (Calendula officinalis): California poppy (Eschscholzia californica): Cornflower (Centaurea cyanus): Dandelion (Taraxacum): Honesty (Lunaria annua)
Nasturtium (Tropaeolum majus): Opium poppy (Papaver somniferum): Phacelia tanacetifolia: Poached egg flower (Limnanthes douglasii): Pot marigold (Calendula officinalis): Sunflower (Helianthus annuus): Teasel (Dipsacus fullonum):Verbena bonariensis: Welsh poppy (Meconopsis cambrica)
A few “must haves”
Thyme (Thymus vulgaris): Sage (salvia officinalis): Queen Anne’s Lace (Ammi visnaga): Cosmos (Cosmos bipinnatus):Coastal Daisy (Erigeron glaucus)
I haven't got onto trees and shrubs yet really.