The guide below compliments our flower seed sowing guide, with additional information on height, sun exposure, bloom time and toxicity to cats, dogs and people.
| Height | Sun exposure | Flowers | Toxic? | |
| African daisy (Arctotis stoechadifolia) | 30 cm | Full sun | Late spring/early summer | Non-toxic |
| African daisy (Osteospermum spp.) | 30 – 90 cm | Full sun | Early summer | Non-toxic |
| Alyssum (Lobularia maritima) | 7 cm | Full sun/partial shade | Spring to autumn | Non-toxic |
| Amethist flower (Browallia spp.) | 30 – 90 cm | Full sun/partial shade | Summer/autumn | Toxic |
| Aster (Aster spp.) | 30 – 120 cm | Full sun | Late summer/mid autumn | Non-toxic |
| Baby’s breath (Gypsophila spp.) | 15 – 90 cm | Full sun | Summer/autumn | Non-toxic |
| Balloon flower (Platycodon grandiflorus) | 30 – 90 cm | Full sun/part shade | Late spring/summer | Toxic |
| Bear’s breeches (Acanthus mollis) | 90 – 120 cm | Full sun/part shade | Late spring/summer | Unknown |
| Bee balm (Monarda didyma) | 90 – 120 cm | Full sun/dappled shade | Late spring/early summer | Non-toxic |
| Begonia (Begonia spp.) | 15 – 60 cm | Part shade | Mid summer/autumn | Toxic |
| Bellflower (Campanula spp.) | 120 cm | Full sun | Spring/mid-summer | Non-toxic |
| Bells-of-Ireland (Moluccella laevis) |
100 cm | Full sun | Summer | Non-toxic |
| Black-eyed Susan (Rudbeckia hirta) | 60 – 90 cm | Full sun/part shade | Late summer/autumn | Toxic |
| Bleeding heart (Dicentra spectabilis) | 75 – 90 cm | Part/full shade | Late spring/summer | Toxic |
| Blanket flower (Gaillardia x grandiflora) |
40 cm | Full sun | Early summer/autumn | Non-toxic |
| Boltonia (Boltonia spp.) | 150 – 180 cm | Full sun | Late summer/early autumn | Unknown |
| Borage (Borago officinalis) | 50 – 90 cm | Full sum/part shade | Early summer/early autumn | Cats and dogs, not humans |
| Bugloss (Anchusa capensis) | 60 cm | Full sun/part shade | Summer | No |
| Butter daisy (Melampodium paludosum) |
20 – 40 cm | Full sun | Summer | Unknown |
| Butterfly flower (Schizanthus spp.) | 30 – 50 cm | Full sun | Spring to autumn | Non-toxic |
| Butterfly pea (Clitoria ternatea) |
3 metres | Full sun | Mid to late summer | Non-toxic |
| Butterfly weed (Asclepias tuberosa) | 30 – 60 cm | Full sun | Late spring and summer | Toxic |
| Calendula (Calendula officinalis) | 80 cm | Full sun | Spring and summer | Non-toxic |
| Californian poppy (Eschscholzia californica) | 20 cm | Full sun | Late spring to summer | Non-toxic |
| Candytuft (Iberis spp.) | 30 cm | Full sun | Spring and summer | Toxic |
| Canterbury bells (Campanula medium) | 60 – 90 cm | Full sun/part shade | Summer | Non-toxic |
| Cape jewels (Nemesia strumosa) | 30 cm | Full sun/part shade | Late spring to autumn | Non-toxic |
| Carnation (Dianthus spp.) | 30 – 50 cm | Full sun | Late spring to summer | Toxic |
| Catnip/catmint (Nepeta spp.) | 30 – 50 cm | Full sun | Late spring to autumn | Non-toxic |
| Chamomile (Matricaria chamomilla) | 50 – 80 cm | Full sun | Mid to late summer | Toxic to cats and dogs, not humans |
| Chilean bellflower (Lapageria rosea) |
1 metre | Full sun/part shade | Late summer and autumn | Unknown |
| Chinese aster (Callistephus chinensis) | 30 – 90 cm | Full sun/part shade | Late summer and autumn | Non-toxic |
| Chinese forget-me-not (Cynoglossum amabile) |
40 cm | Full sun/part shade | Summer | Toxic |
| Chinese lantern (Physalis alkekengi) | 40 – 60 cm | Full sun/part shade | Summer | Toxic |
| Chrysanthemum (Chrysanthemum spp.) | 40 – 100 cm | Full sun | Summer to autumn | Toxic |
| Clematis (Clematis spp.) | 2.4 – 3.6 metres | Full sun | Spring | Toxic |
| Cliquefoil (Potentilla spp.) | 30 – 90 cm | Full sun/part shade | Late spring to autumn | Non-toxic |
| Cohosh (Cimicifuga spp.) | 25 – 60 cm | Part to full shade | Late summer to early autumn | Unknown |
| Columbine (Aquilegia spp.) | 30 – 45 cm | Full sun | Spring | Yes |
| Common rockrose (Helianthemum nummularium) | 15 – 30 cm | Full sun | Spring and summer | Unknown |
| Common sneezeweed (Helenium autumnale) | 90 cm | Full sun | Autumn | Toxic |
| Coral bell (Heuchera spp.) | 20 – 30 cm | Full sun/part shade | Spring to autumn | Non-toxic |
| Corncockle (Agrostemma githago) | 30 – 60 cm | Full sun | Summer | Toxic |
| Cornflower (Centaurea cyanus) | 90 cm | Full sun | Spring to summer | Non-toxic |
| Cosmos (Cosmos bipinnatus) | 90 cm to 1.5 metres | Full sun | Summer | Non-toxic |
| Cup and saucer vine (Cobaea scandens) | 1.5 to 3 metres | Full sun | Late summer | Non-toxic |
| Cupflower (Nierembergia spp.) | 5 cm | Full sun/part shade | Mid-summer to mid-autumn | Toxic |
| Cupid’s bow (Achimenes spp.) | 30 cm | Bright/indirect sun | Summer to autumn | Non-toxic |
| Cupid’s dart (Catananche caerulea) | 18 – 28 cm | Full sun | Mid-summer to autumn | Non-toxic |
| Cyclamen (Cyclamen spp.) | 20 cm | Part shade | Late winter to spring | Toxic |
| Dahlberg daisy (Thymophylla tenuiloba) |
15 – 30 cm | Full sun | Summer to early autumn | Toxic |
| Dahlia (Dahlia spp.) | 15 cm to 1.2 metres | Full sun | Late summer to autumn | Mildly toxic to cats and dogs, not humans |
| Delphinium (Delphinium elatum) | 100 – 150 cm | Full sun | Spring and summer | Toxic |
| Echinacea (Echinacea spp.) | 75 – 120 cm | Full sun/part shade | Summer and autumn | Non-toxic |
| Edeiweiss (Leontopodium alpinum) |
15 – 20 cm | Full sun | Late spring and summer | Unknown |
| English daisy (Bellis perennis) | 20 – 30 cm | Full sun/part shade | Spring and summer | Non-toxic |
| Evening primrose (Oenothera spp.) | 90 – 150 cm | Full sun | Late spring to early autumn | Toxic to cats and dogs, not humans |
| Everlasting (Helichrysum bracteatum) | 100 – 150 cm | Full sun | Spring and summer | Unknown |
| False sunflower (Heliopsis spp.) | 60 – 120 cm | Full sun | Summer | Non-toxic |
| Fan flower (Scaevola aemula) | 50 cm | Full sun/part shade | Summer to autumn | Non-toxic |
| Feverfew (Tanacetum parthenium) |
70 cm | Full sun/part shade | Summer to autumn | Unknown |
| Firecracker flower (Crossandra infundibuliformis) | 30 – 90 cm | Part shade | Spring to autumn | Non-toxic |
| Flax (Linum usitatissimum) | 30 – 100 cm | Full sun | Summer | Non-toxic |
| Fleabane (Erigeron spp.) | 20 – 30 cm | Full sun | Spring to autumn | Toxic |
| Floss flower (Ageratum houstonianum) | 30 – 100 cm | Full sun | Summer | Toxic |
| Forget-me-non toxict (Myosotis spp.) | 30 cm | Part shade | Spring | Non-toxic |
| Foxglove (Digitalis spp.) | 60 – 90 cm | Full sun/part shade | Spring and summer | Toxic |
| Garden heliotrope (Heliotropium spp.) | 10 – 50 cm | Full sun | Spring to late summer | Toxic |
| Gay feather (Liatris spp.) | 90 – 150 cm | Full sun/part shade | Mid to late summer | Non-toxic |
| Gazania (Gazania spp.) | 30 cm | Full sun/part shade | Spring to autumn | Non-toxic |
| Geranium (Pelargonium spp.) |
30 – 90 cm | Full sun/part shade | Spring to autumn | Toxic |
| Gerbera (Gerbera spp.) | 75 cm | Full sun | Late spring to autumn | Non-toxic |
| Geum (Geum spp.) | 30 – 90 cm | Part shade | Spring | Unknown |
| Globeflower (Trollius spp.) | 60 cm | Shade | Mid-spring to early summer | Non-toxic |
| Gloxinia (Sinningia speciosa) | 20 – 30 cm | Part shade | Late spring to autumn | Non-toxic |
| Goldencup (Hunnemannia fumariifolia) | 60 cm | Full sun | Mid-summer to early autumn | Unknown |
| Goldenrod (Solidago spp.) | 60 cm to 2.4 metres | Full sun | Mid to late summer | Non-toxic |
| Goldentuft (Aurinia saxatilis) | 5 – 10 cm | Full sun | Spring to early summer | Non-toxic |
| Hellebore (Helleborus spp.) | 30 cm | Part sun/dappled shade | Winter to spring | Toxic |
| Hibiscus (Hibiscus spp.) | 1 – 2 metres | Full sun | Mid to late summer | Non-toxic |
| Hollyhock (Alcea rosea) | 1.5 metres | Full sun | Summer | Non-toxic |
| Iceland poppy (Papaver nudicaule) | 30 – 45 cm | Full sun | Spring to early summer | Toxic |
| Impatiens (Impatiens spp.) | 1 metre | Full sun | Spring to autumn | Non-toxic |
| Jacob’s ladder (Polemonium spp.) | 45 – 60 cm | Full sun/part shade | Late spring to early summer | Non-toxic |
| Laceflower (Trachymene coerulea) | 80 cm | Full sun/part shade | Spring to summer | Unknown |
| Ladys purse (Calceolaria spp.) | 70 – 90 cm | Full sun/part shade | Early spring to summer | Non-toxic |
| Larkspur (Consolida ambigua) | 30 – 120 cm | Part sun/part shade | Summer | Toxic |
| Lavender (Lavandula spp.) | 30 – 90 cm | Full sun | Spring and summer | Toxic |
| Leopard plant (Ligularia spp.) | 30 cm | Part sun | Late summer | Non-toxic |
| Leopard’s bane (Doronicum cordatum) |
20 – 90 cm | Full sun/part shade | Summer to autumn | Toxic |
| Linaria (Linaria spp.) | 15 – 90 cm | Full sun | Late spring to late summer | Non-toxic |
| Lisianthus (Eustoma grandiflorum) | 15 – 60 cm | Full sun/part shade | Summer to autumn | Non-toxic |
| Livingstone daisy (Dorotheanthus bellidiformis) |
15 cm | Full sun | Spring | Non-toxic |
| Lobelia (Lobelia spp.) | 15 – 20 cm | Full sun/part shade | Spring to autumn | Toxic |
| Love-lies-bleeding (Amaranthus caudatus) | 90 – 120 cm | Full sun | Mid-summer to autumn | Non-toxic |
| Lupine (Lupinus spp.) | 90 cm | Full sun | Early summer | Toxic |
| Madagascar periwinkle (Catharanthus roseus) |
50 cm | Full sun/part shade | Late spring to autumn | Toxic |
| Maltese cross (Lychnis chalcedonica) |
30 – 50 cm | Full sun/part shade | Summer | Non-toxic |
| Marigold (Tagetes spp.) | 30 cm | Full sun/part shade | Summer to autumn | Toxic |
| Marshmallow plant (Althaea officinalis) | 90 cm to 1.2 metres | Full sun | Mid-summer | Non-toxic |
| Meadowsweet (Filipendula ulmaria) |
1 metre | Full sun/part shade | Late summer | Non-toxic |
| Mexican creeping zinnia (Sanvitalia procumbens) |
20 cm | Full sun | Summer to early autumn | Non-toxic |
| Mexican sunflower (Tithonia spp.) |
60 cm to 1.2 metres | Full sun | Summer | Non-toxic |
| Mignon toxicnette (Reseda odorata) | 30 cm | Full sun/part shade | Mid-summer to early autumn | Unknown |
| Monkey flowers (Mimulus spp.) | 15 cm | Full sun/part shade | Summer | Non-toxic |
| Monk’s hood (Aconitum spp.) | 1 metre | Full sun/part shade | Mid-summer | Toxic |
| Morning glory (Convolvulus spp.) |
2 metres | Full sun | Summer to autumn | Toxic |
| Mullein (Verbascum) | 30 cm to 1.2 metres | Full sun/part shade | Spring to summer | Toxic |
| Musk mallow (Malva moschata) |
60 cm | Full sun | Early summer to autumn | Non-toxic |
| Nasturtium (Tropaeolum majus) | 30 – 300 cm | Full sun | Spring to autumn | Non-toxic |
| Nemesia (Nemesia spp.) | 30 – 60 cm | Full sun | Spring and autumn | Non-toxic |
| Nemophila (Nemophila spp.) | 15 – 30 cm | Full sun/part shade (warm areas) | Mid-summer to late autumn | Unknown |
| Nigella (Nigella damascena) | 30 – 45 cm | Full sun/part shade | Spring | Mildly toxic |
| Obedient plant (Physostegia virginiana) | 90 – 120 cm | Full sun/part shade | Mid to late summer | Non-toxic |
| Pansy (Viola tricolor var. hortensis) | 20 cm | Full sun/part shade | Spring to summer | Mildly toxic |
| Pearly everlasting (Anaphalis margaritacea) | 30 – 90 cm | Full sun | Summer | Non-toxic |
| Persian violet (Exacum affine) | 20 – 30 cm | Morning sun | Spring to autumn | Non-toxic |
| Petunia (Petunia spp.) | 30 cm | Full sun | Summer | Non-toxic |
| Phlox (Phlox spp.) | 45 cm | Full sun | Summer to autumn | Non-toxic |
| Poppy (Papaver spp.) | 45 cm | Full sun | Spring | Toxic |
| Portulaca (Portulaca spp.) | 10 – 20 cm | Full sun | Summer | Toxic |
| Pride of Madeira (Echium candicans) | 1.5 – 2 metres | Full sun | Spring | Toxic |
| Primrose (Primula spp.) | 25 – 30 cm | Part shade | Spring | Toxic |
| Purple rock cress (Aubrieta deltoidea) | 10 – 20 cm | Full sun/part shade | Spring | Unknown |
| Queen Anne’s lace (Daucus carota) | 30 – 120 cm | Full sun | Mid-summer to mid-autumn | Toxic |
| Rock cress (Arabis spp.) | 10 – 20 cm | Full sun | Spring | Unknown |
| Salvia (Salvia officinalis) | 20 cm | Full sun | Mid-summer to mid-autumn | Non-toxic |
| Satin flower (Clarkia amoena) | 1 metre | Morning sun | Late spring to early summer | Unknown |
| Shooting star (Dodecatheon meadia) | 60 cm | Filtered shade | Mid spring | Non-toxic |
| Sea holly (Eryngium spp.) | 20 – 60 cm | Full sun | Summer to autumn | Toxic |
| Shasta daisy (Leucanthemum x superbum) | 60 – 90 cm | Full sun/part shade | Mid-summer to mid-autumn | Toxic |
| Snapdragon (Antirrhinum majus) | 60 cm | Full sun/part shade | Spring and autumn | Non-toxic |
| Snow-in-summer (Cerastium tomentosum) | 20 – 30 cm | Full sun/part shade | Late spring to early summer | Non-toxic |
| Speedwell (Veronica spp.) | 140 cm | Full sun/part shade | Spring to autumn | Toxic |
| Spider flower (Cleome hassleriana) |
150 cm | Full sun/part shade | Early summer to autumn | Non-toxic |
| Statice (Limonium sinuatum) | 50 cm | Full sun | Summer to autumn | Non-toxic |
| Stock (Matthiola incana) | 20 – 30 cm | Full sun to light shade | Late winter to spring | Non-toxic |
| Stoke’s aster (Stokesia laevis) | 150 cm | Full sun/part shade | Summer | Non-toxic |
| Sunflower (Helianthus spp.) | 30 cm – 1.8 metres | Full sun | Summer | Non-toxic |
| Swan river daisy (Brachyscome iberidifolia) | 30 cm | Full sun | Summer | Toxic |
| Sweet pea (Lathyrus odoratus) | 200 cm | Full sun | Summer | Toxic |
| Sweet rocket (Hesperis matronalis) |
80 cm | Full sun/part shade | Mid-spring to mid-summer | Non-toxic |
| Trumpet flower (Incarvillea spp.) | 30 – 40 cm | Full sun/part shade | Late spring to early summer | Non-toxic |
| Tweedia (Oxypetalum coeruleum) | 100 cm | Full sun | Spring and summer | Yes |
| Twinspur (Diascia spp.) | 25 – 40 cm | Full sun | Spring to autumn | No |
| Verbena (Verbena spp.) | 30 – 45 cm | Full sun | Early summer to autumn | Yes |
| Viola (Viola spp.) | 30 cm | Full sun (part shade in hot climates) |
Early summer to autumn | No |
| Virginian stock (Malcolmia maritima) | 15 – 30 cm | Full sun | Mid-summer to autumn | Unknown |
| Wallflower (Erysimum cheiri, syn. Cheiranthus cheiri) | 45 – 60 cm | Full sun | Spring to summer | No |
| Wild indigo (Baptisia spp.) | 90 – 120 cm | Full sun | Late spring to early summer | No |
| Wishbone flower (Torenia fournieri) | 15 – 30 cm | Part shade | Late spring to early summer | Unknown |
| Xeranthemum (Xeranthemum annuum) | 40 – 60 cm | Full sun | Summer to early autumn | Unknown |
| Yarrow (Achillea spp.) | 60 – 90 cm | Full sun | Summer to autumn | Yes |
| Zinnia (Zinnia spp.) | 120 cm | Full sun | Summer to autumn | No |
