Seed list and germination guide

Discover the joy of growing from seed with the RHS Members’ Seed Scheme, a curated collection of inspiring plant varieties paired with expert germination know-how to help every seed get off to a flying start

RHS Seed Collections 2027

Browse the seed list to choose what to grow at home, supported by germination information for every plant:

RHS Gardens | Award winners | Easy choices | Seasonal colour | Perennial beauty | Wildlife friendly | Naturalistic planting | Structural interest | Shade solutions | Drought tolerant | Practical | Specialist picks

RHS Garden favourites

Hand-picked from the planting inspiration found across the five RHS Gardens

RHS Garden Wisley Collection (available at RHS Wisley only)

Germination requirements: RHS Garden Wisley Collection

Amsonia tabernaemontana var. salicifolia (eastern bluestar)

  • Sow seeds in autumn or spring
  • Surface-sow the seeds and gently press them into the compost
  • Do not cover the seeds, as they need light to germinate
  • Keep at 13–16°C.
  • Germination can take up to 90 days

Cichorium intybus (chicory)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 10–15°C
  • Germination should occur within 30 days

Hydrangea paniculata (panicled hydrangea)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them
  • Keep at 13–16°C
  • Germination can take more than 90 days

Stipa gigantea (golden oats)

  • Sow seeds in spring
  • Use a well-drained seed compost
  • Keep at 18–21°C
  • Germination can take 30–90 days

Veronicastrum virginicum f. roseum (rosy Culver’s root)

  • Sow seeds and leave them uncovered, as they need light to germinate
  • Keep at 16–21°C
  • Germination can take up to 90 days

RHS Garden Bridgewater Collection (available at RHS Bridgewater only)

Germination requirements: RHS Garden Bridgewater Collection

Astrantia major (greater masterwort)

  • Place seeds in a cold, moist environment for four weeks before sowing
  • Sow the seeds and leave them uncovered, as they need light to germinate
  • Keep at 13–18°C
  • Germination can take up to one year

Deschampsia cespitosa (tufted hair grass)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 20°C
  • Germination should occur within 30 days

Digitalis purpurea (common foxglove)

  • Sow seeds in late spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15°C
  • Germination can take 30–90 days

Echinacea purpurea (purple coneflower)

  • Sow seeds in spring or autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 13°C
  • Germination should occur within 90 days

Molinia caerulea subsp. arundinacea (purple moor-grass)

  • Sow seeds in autumn
  • Lightly cover the seeds with compost
  • Seeds require a period of cold, moist stratification
  • Keep at 10–15°C
  • Germination should occur within six months

RHS Garden Hyde Hall Collection (available at RHS Hyde Hall only)

Germination requirements: RHS Garden Hyde Hall Collection

Dianthus carthusianorum (German pink)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Use a well-drained seed compost
  • Keep at 15–20°C
  • Germination can take up to 90 days

Miscanthus sinensis (eulalia)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them
  • Keep at 15–20°C
  • Germination can take up to 90 days
  • If germination is poor, try a period of cold, moist stratification

Pennisetum villosum (feathertop)

  • Sow seeds in spring
  • Use a well-drained seed compost
  • Keep at 18–21°C
  • Germination should occur within 30 days

Rudbeckia fulgida (black-eyed Susan)

  • Sow seeds and lightly cover with compost
  • Keep at 16–18°C
  • Germination should occur within 30 days
  • If germination is poor, place the seeds in a cold, moist environment for four weeks, then return them to warmth

Helleborus × hybridus (hybrid Lenten rose)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 16–18°C
  • Germination can take up to one year

RHS Garden Rosemoor Collection (available at RHS Rosemoor only)

Germination requirements: RHS Garden Rosemoor Collection

Asphodeline liburnica (Liburne asphodel)

  • Sow seeds at any time of year
  • Cover the seeds with a very thin layer of compost
  • Seeds need light to germinate, so do not cover them deeply
  • Seeds can be sown directly where they are to grow
  • Avoid disturbing seedlings once established
  • Keep at 15–20°C
  • Germination can take 30–90 days

Corynabutilon × suntense (Gorer’s mallow)

  • Sow seeds in spring
  • Keep at around 25°C
  • Germination can be slow and uneven, taking several months or longer
  • If seeds have not germinated after 4–6 weeks, place them in a cold, moist environment for 4–6 weeks, then return them to warmth

Eryngium planum (blue eryngo)

  • Moisten the seeds and place them on a piece of damp kitchen paper
  • Place the kitchen paper in a sealed plastic bag
  • Keep at 15°C
  • Germination should occur within 30 days

Stipa ichu (ichu)

  • Sow seeds in spring
  • Use a well-drained seed compost
  • Keep at 18–21°C
  • Germination can take 30–90 days

Verbascum bombyciferum (Broussa mullein)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 15–18°C
  • Germination should occur within 14–21 days

RHS Garden Harlow Carr Collection (available at RHS Harlow Carr only)

Germination requirements: RHS Garden Harlow Carr Collection

Centaurea cyanus (cornflower)

  • Sow seeds directly where they are to grow from early spring
  • Use any well-drained soil
  • Sow seeds thinly and lightly cover with soil
  • Keep at 10–15°C
  • Germination should occur within 30 days

Cyclamen hederifolium (ivy-leaved cyclamen)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Before sowing, it can help to soak the seeds in cold water for 10 hours
  • Seeds may need two cold periods before they will germinate
  • Keep at 10–15°C
  • Germination can take up to one year

Silene flos-cuculi (ragged robin)

  • Sow seeds directly where they are to grow in early spring or autumn
  • Lightly cover the seeds with soil
  • Keep at 16–21°C
  • Germination should occur within 30 days

Stipa tenuissima (Mexican feather grass)

  • Sow seeds in spring
  • Use a well-drained seed compost
  • Keep at 18–21°C
  • Germination can take 30–90 days

Digitalis ferruginea (rusty foxglove)

  • Sow seeds in late spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15°C
  • Germination can take 30-90 days

Award winners

Proven performers that never disappoint, with accolades to match their brilliance

RHS Recommended: AGM Collection

Germination requirements: RHS Recommended: AGM Collection

Ammi majus (false bishop’s weed)

  • Sow seeds in spring or autumn
  • Use a well-drained seed compost
  • Keep at 16–21°C
  • Germination can be slow or uneven
  • Allow up to 21 days for germination

Chionochloa rubra (red tussock grass)

  • Sow seeds in autumn
  • Surface-sow the seeds and do not cover them
  • Seeds require a period of cold, moist stratification
  • Keep at around 20°C once conditions warm
  • Germination can be uneven, but should occur when temperatures rise in spring

Nicotiana langsdorffii (Langsdorff’s tobacco plant)

  • Sow seeds and leave them uncovered, as they need light to germinate
  • Keep at 18–20°C
  • Germination can take up to 90 days

Calamagrostis brachytricha (Korean feather reed grass)

  • Sow seeds in spring
  • Sow on the surface and lightly cover with compost
  • Keep at 20°C
  • Germination should occur within 30 days

Cenolophium denudatum (Baltic parsley)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Very lightly cover the seeds with compost, as they need light to germinate
  • Keep at 15–20°C
  • Germination can take up to one year

Easy choices

Beautiful gardens made simple with dependable plants that are easy to grow

Easy-to-Grow Collection

Germination requirements: Easy-to-Grow Collection

Amaranthus hypochondriacus (prince’s feather)

  • Sow seeds directly where they are to flower in late spring
  • Keep at 22°C
  • Germination should occur within 10–20 days

Hesperis matronalis (dame’s violet)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 18–21°C
  • Germination should occur within 30 days

Phacelia tanacetifolia (fiddleneck)

  • Sow seeds directly outdoors between March and September
  • Keep at 10–16°C
  • Germination should occur within 30 days

Tithonia rotundifolia (Mexican sunflower)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Do not exclude light after sowing
  • Keep at 13–18°C
  • Germination should occur within 7–21 days

Valeriana officinalis (common valerian)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15–18°C
  • Germination should occur within 30 days

Seasonal colour

Fill beds, borders and containers with plants chosen for months of colourful display

Annuals Collection

Germination requirements: Annuals Collection

Alcea ficifolia (Antwerp hollyhock)

  • Sow seeds in spring
  • Lightly cover the seeds with a thin layer of compost
  • Keep at 16–21°C
  • Germination can take up to 90 days

Amaranthus cruentus (purple amaranth)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 21–24°C
  • Germination can take up to 90 days

Bupleurum rotundifolium (thorow-wax)

  • Sow seeds directly where they are to flower
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Germination can take 14–60 days

Cosmos bipinnatus (cosmea)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 15–20°C
  • Germination should occur within 30 days

Nicotiana glutinosa (Peruvian tobacco)

  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 18–20°C
  • Germination can take up to 90 days

Cut Flowers Collection

Germination requirements: Cut Flowers Collection

Atriplex hortensis var. rubra (red mountain spinach)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Seeds can also be sown directly outdoors into prepared soil
  • Keep at 15°C
  • Germination should occur within 30 days

Cosmos sulphureus (yellow cosmos)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 16–21°C
  • Germination should occur within 30 days

Gypsophila paniculata (baby’s breath)

  • Sow seeds in spring or autumn
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Seeds can also be sown directly where they are to grow
  • Keep at 18–22°C
  • Germination should occur within 5–10 days

Nigella papillosa (papillose-leaved love-in-a-mist)

  • Sow seeds directly where they are to grow in mid-spring or autumn
  • Lightly cover the seeds with soil
  • If sowing in autumn, provide winter protection for seedlings if needed
  • Keep at 13–18°C
  • Germination should occur within 90 days

Panicum capillare (witch grass)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 16–21°C
  • Germination can take up to six months

Perennial beauty

Reliable herbaceous perennials that return year after year with colour and interes

Herbaceous Hot Collection

Germination requirements: Herbaceous Hot Collection

Kniphofia mixed (red-hot poker)

  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 13–18°C
  • Germination can take up to 90 days

Hesperantha coccinea (crimson flag-lily)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Sow directly into a suitable container, as the plant dislikes root disturbance
  • Keep at 13–16°C
  • Germination can take up to 90 days

Rudbeckia californica (California coneflower)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 16–18°C
  • Germination should occur within 30 days
  • If germination is poor, place the seeds in a cold, moist environment for four weeks, then return them to warmth

Silene coronaria Atrosanguinea Group (rose campion Atrosanguinea Group)

  • Sow seeds directly where they are to grow in early spring or autumn
  • Lightly cover the seeds with soil
  • Keep at 16–21°C
  • Germination should occur within 30 days

Verbascum phoeniceum (purple mullein)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 15–18°C
  • Germination should occur within 30 days

Herbaceous Cool Collection

Germination requirements: Herbaceous Cool Collection

Adenophora pereskiifolia (pereskia-leaved ladybells)

  • Sow seeds directly into a suitable container, as the plant dislikes root disturbance
  • A period of cold treatment may improve germination
  • Keep at 10–13°C
  • Germination can take 30–90 days

Digitalis lutea (small yellow foxglove)

  • Sow seeds in spring or summer
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15°C
  • Germination can take 30–90 days

Lunaria rediviva (perennial honesty)

  • Sow seeds in summer
  • Cover the seeds with 3mm of compost
  • Keep at 15–20°C
  • Germination can be slow and uneven
  • Seeds may require a period of cold, moist stratification
  • Germination can take up to 90 days

Salvia napifolia (Turkish sage)

  • Sow seeds in spring
  • Leave the seeds uncovered when sowing
  • Keep at 18–24°C
  • Germination should occur within 30 days

Veronica longifolia (garden speedwell)

  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 13–18°C
  • Germination can take up to 90 days

Wildlife friendly

Support bees, butterflies and other pollinators with plants rich in nectar and pollen

Plants for Pollinators Collection

Germination requirements: Plants for Pollinators Collection

Agastache rugosa (Korean mint)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 10–16°C
  • Germination can take 30–90 days

Daucus carota (wild carrot)

  • Sow seeds directly where they are to grow from early spring to summer
  • Use any well-drained soil
  • Protect early sowings from frost
  • Sow seeds thinly and lightly cover with soil
  • Keep at 10–15°C
  • Germination should occur within 30 days

Erysimum cheiri (common wallflower)

  • Sow seeds in late summer for spring flowers, or late winter for autumn flowers
  • Lightly cover the seeds with compost
  • Keep at 16–18°C
  • Germination should occur within 30 days

Nicotiana sylvestris (woodland tobacco plant)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them
  • Keep at 18–22°C
  • Germination should occur within 20 days

Oenothera biennis (common evening primrose)

  • Sow seeds in spring or autumn
  • Lightly cover the seeds with compost
  • Keep at 18–20°C
  • Germination should occur within 30 days
  • Seeds may benefit from a period of cold, moist stratification if germination is slow

Naturalistic planting

Bring a touch of the wild home with naturalistic plantings inspired by meadows, prairies and cottage gardens

Prairie Plants Collection

Germination requirements: Prairie Plants Collection

Amsonia tabernaemontana (eastern bluestar)

  • Sow seeds between February and July
  • Surface-sow the seeds and gently press them into the compost
  • Do not cover the seeds, as they need light to germinate
  • Keep at 13–16°C
  • Germination can take up to 90 days

Asclepias incarnata (swamp milkweed)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 20°C
  • Germination should occur within 30 days

Echinacea pallida (pale purple coneflower)

  • Sow seeds in spring or autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 13°C
  • Germination should occur within 90 days

Pennisetum villosum (feathertop)

  • Sow seeds in spring
  • Use a well-drained seed compost
  • Keep at 18–21°C
  • Germination should occur within 30 days

Veronicastrum sibiricum (Siberian Culver’s root)

  • Sow seeds and leave them uncovered, as they need light to germinate
  • Keep at 16–21°C
  • Germination can take up to 90 days

Meadow Mix Collection

Germination requirements: Meadow Mix Collection

Agrostemma githago (corncockle)

  • Sow seeds directly where they are to flower
  • Lightly cover the seeds with soil
  • Keep at 13–16°C
  • Germination can take 30–90 days

Centaurea nigra (common knapweed)

  • Sow seeds directly where they are to grow from early spring
  • Use any well-drained soil
  • Sow seeds thinly and lightly cover with soil
  • Keep at 10–15°C
  • Germination should occur within 30 days

Glebionis segetum (corn marigold)

  • Sow seeds indoors in spring or directly outdoors later in the season
  • Keep at 16–21°C
  • Germination should occur within 10–14 days

Nigella damascena (love-in-a-mist)

  • Sow seeds directly where they are to grow in mid-spring or autumn
  • Lightly cover the seeds with soil
  • If sowing in autumn, provide winter protection for seedlings if needed
  • Keep at 13–18°C
  • Germination should occur within 90 days

Papaver rhoeas (common poppy)

  • Sow seeds directly where they are to grow in spring
  • Lightly cover the seeds with soil
  • Keep at 13–18°C
  • Germination can take up to 90 days

Cottage Garden Plants Collection

Germination requirements: Cottage Garden Plants Collection

Alcea rosea (hollyhock)

  • Sow seeds in spring
  • Lightly cover the seeds with a thin layer of compost
  • Keep at 16–21°C
  • Germination can take up to 90 days

Cephalaria gigantea (giant scabious)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 15°C
  • Germination should occur within 90 days

Knautia macedonica (Macedonian scabious)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Surface-sow the seeds and cover very lightly with grit
  • Keep the compost moist
  • Keep at 10–16°C
  • Germination can be slow and uneven
  • Germination can take up to 90 days

Orlaya grandiflora (white laceflower)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 18°C
  • Germination should occur within 21–30 days, but can take longer
  • If seeds have not germinated after 6–8 weeks, try a period of cold, moist stratification

Phlox paniculata (perennial phlox)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 15–18°C
  • Germination should occur within 30 days

Structural interest

Add height, shape and year-round interest with plants that bring structure and character

Architectural Plants Collection

Germination requirements: Architectural Plants Collection

Angelica archangelica (angelica)

  • Sow seeds in spring or autumn
  • Seeds can be sown directly where they are to grow
  • Lightly cover the seeds with compost, as they need light to germinate
  • Transplant seedlings while they are still small, as larger plants dislike disturbance
  • Keep at 10–15°C
  • Germination can take 30–90 days

Eryngium giganteum (Miss Willmott’s ghost)

  • Moisten the seeds and place them on a piece of damp kitchen roll
  • Place the kitchen roll in a sealed plastic bag
  • Keep at 15°C
  • Germination should occur within 30 days

Glycyrrhiza yunnanensis (Yunnan liquorice)

  • Before sowing, soak the seeds in cold water for 24 hours
  • Sow seeds in spring
  • Keep at 15–18°C
  • Germination can take 30–90 days

Peucedanum verticillare (giant hog fennel)

  • Sow seeds in autumn
  • Lightly cover the seeds with compost
  • Ideally keep pots in a cold frame over winter
  • Allow natural cold and warming temperatures to help trigger germination in spring
  • Keep at 5–12°C
  • Germination occurs as conditions become suitable in spring

Rudbeckia maxima (great coneflower)

  • Sow seeds and lightly cover with compost
  • Keep at 16–18°C
  • Germination should occur within 30 days
  • If germination is poor, place the seeds in a cold, moist environment for four weeks, then return them to warmth

Exotic Plants Collection

Germination requirements: Exotic Plants Collection

Decaisnea fargesii (blue bean shrub)

  • Sow seeds in autumn
  • Use a well-drained seed compost
  • Keep at 16–18°C
  • Germination can be slow and uneven
  • Germination can take more than 90 days

Eccremocarpus scaber (Chilean glory flower)

  • Sow seeds in early spring
  • Lightly cover the seeds with compost
  • Keep at 13–16°C
  • Germination can be slow and uneven
  • Germination should occur within 90 days

Eucomis comosa (pineapple lily)

  • Sow seeds from spring to early summer
  • Lightly cover the seeds, as some light is needed for germination
  • Keep at 18–24°C
  • Germination can be slow
  • Germination can take up to one year

Akebia quinata (chocolate vine)

  • Scarify the seeds and soak them in water for 24 hours before sowing
  • Sow seeds 5mm deep and space them well apart
  • Keep at 20–24°C
  • Germination can be slow and uneven

Tigridia pavonia (peacock tiger flower)

  • Sow seeds in spring
  • Sow directly outdoors or into individual modules, as the plant dislikes root disturbance
  • Keep at 15°C
  • Germination can take up to one year

Shade solutions

Brighten shady spots with plants suited to dry, moist and partially shaded conditions

Plants for Shade Collection

Germination requirements: Plants for Shade Collection

Aquilegia vulgaris mixed (common columbine)

  • Sow seeds in autumn
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Seeds require a period of cold, moist stratification
  • Keep at 15–21°C
  • Germination can be slow and uneven
  • Germination can take 1–3 months

Digitalis trojana (Helen of Troy foxglove)

  • Sow seeds in spring or summer
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15°C
  • Germination can take 30–90 days

Hydrangea bifida (two-lobed false hydrangea)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them
  • Keep at 13–16°C
  • Germination can be slow and uneven
  • Germination can take more than 90 days

Thalictrum flavum subsp. glaucum (glaucous-leaved yellow meadow rue)

  • Sow seeds in autumn
  • Cover the seeds lightly with grit
  • Seeds require a period of cold, moist stratification
  • Keep at 13–18°C
  • Germination should occur within 30 days

Trochodendron aralioides (wheel tree)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 13–16°C
  • Germination can take more than 90 days

Plants for Dry Shade Collection

Germination requirements: Plants for Dry Shade Collection

Alchemilla mollis (lady’s mantle)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 18–22°C for 2–4 weeks
  • Germination should occur within 30 days
  • If germination does not occur, place the seeds in a cold, moist environment before returning them to warmth

Anemanthele lessoniana (pheasant's tail grass)

  • Sow seeds in spring or autumn
  • Cover the seeds very lightly with compost
  • Keep at 18–21°C
  • Germination can take 30–90 days

Heuchera villosa (hairy alum root)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15–20°C
  • Germination can take up to 90 days

Campanula latifolia (giant bellflower)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15–20°C
  • Germination can take up to 90 days

Tellima grandiflora (fringe cups)

  • Sow seeds in autumn or spring
  • Lightly cover the seeds with compost
  • Keep at 16–21°C
  • Germination can take more than 90 days

Plants for Moist Shade Collection

Germination requirements: Plants for Moist Shade Collection

Hosta sieboldiana (Siebold’s plantain lily)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 10–16°C
  • Germination can take up to 90 days

Iris sibirica (Siberian iris)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 13–18°C
  • Germination can take up to one year

Lobelia × speciosa (cardinal flower hybrid)

  • Surface-sow the seeds and do not cover them
  • Keep the compost consistently moist
  • Keep at 15–20°C
  • Germination can take up to 90 days

Lythrum salicaria (purple loosestrife)

  • Sow seeds in spring or autumn
  • Lightly cover the seeds with compost
  • Seeds can also be sown directly into prepared soil
  • Keep at 15–20°C
  • Germination should occur within 30 days

Primula Candelabra hybrids (primrose Candelabra hybrids)

  • Sow seeds and leave them uncovered, as they need light to germinate
  • Seeds require a period of cold, moist stratification
  • Keep at 13–16°C
  • Germination can take up to 90 days

Drought tolerant

Tough, resilient plants that thrive in sunny, free-draining and drier conditions

Drought-tolerant Collection

Germination requirements: Drought-tolerant Collection

Amsonia hubrichtii (Arkansas bluestar)

  • Sow seeds in autumn or spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 13–16°C
  • Germination can take up to 90 days

Baptisia australis (blue false indigo)

  • Fill pots or trays with a very free-draining seed compost
  • Before sowing, soak the seeds in hot water for 12 hours
  • Sow the seeds and keep at around 20°C
  • Germination is often irregular and unpredictable
  • Allow up to 30 days for germination

Miscanthus nepalensis (Himalayan fairy grass)

  • Sow seeds in spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 21–27°C
  • Germination can take up to 90 days
  • If seeds do not germinate, place them in a cold, moist environment for 2–4 weeks, then return them to warmth

Oenothera lindheimeri (white gaura)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 18–20°C
  • Germination should occur within 30 days

Verbena hastata f. rosea (pink-flowered blue vervain)

  • Sow seeds from autumn to early spring
  • Lightly cover the seeds with compost
  • Keep at 18–21°C
  • Germination can be slow and uneven
  • Allow up to 90 days for germination

Sunny Sites Collection

Germination requirements: Sunny Sites Collection

Asphodelus aestivus (asphodel)

  • Sow seeds into a suitable container, as the plant dislikes root disturbance
  • Lightly cover the seeds with compost
  • Keep at 16–21°C
  • Germination can take 30–90 days

Calendula officinalis (common marigold)

  • Sow seeds directly where they are to grow in spring or autumn
  • Keep at 15°C
  • Germination should occur within 30 days

Libertia chilensis (New Zealand satin flower)

  • Sow seeds in autumn
  • Lightly cover the seeds with compost or grit
  • Seeds require a period of cold, moist stratification
  • Keep at 15–20°C
  • Germination can take up to one year

Papaver somniferum (opium poppy)

  • Sow seeds directly where they are to grow in spring
  • Lightly cover the seeds with soil
  • Keep at 13–18°C
  • Germination can take up to 90 days

Potentilla fruticosa (shrubby cinquefoil)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Do not cover deeply, as the seeds need light to germinate
  • Keep at 18–24°C
  • Germination should occur within 7–14 days

Gravel Garden Collection

Germination requirements: Gravel Garden Collection

Dierama pulcherrimum (angel’s fishing rod)

  • Sow seeds in spring or autumn
  • Use a well-drained seed compost
  • Cover the seeds with compost to twice the depth of the seed
  • Keep at 20°C
  • Germination can be slow and uneven
  • Germination can take up to one year

Dryas × suendermannii (Suendermann dryad)

  • Sow seeds in autumn
  • Lightly cover the seeds with compost
  • Seeds require a period of cold, moist stratification
  • Keep at 15–20°C
  • Germination can be very slow and may take up to six months

Eryngium bourgatii (Mediterranean eryngo)

  • Moisten the seeds and place them on a piece of damp kitchen roll
  • Place the kitchen roll in a sealed plastic bag
  • Keep at 15°C
  • Germination should occur within 30 days

Oenothera stricta (fragrant evening primrose)

  • Sow seeds directly where they are to grow in spring
  • Lightly cover the seeds with soil
  • Keep at 20–25°C
  • Germination should occur within 14–30 days

Scabiosa columbaria subsp. ochroleuca (pale yellow scabious)

  • Sow seeds in autumn
  • Lightly cover the seeds with compost
  • Keep at 16–21°C
  • Germination can be slow and uneven
  • Germination can take up to 90 days

Practical planting

Practical problem-solvers for awkward spaces, from slopes and banks to gaps between plants

Groundcover Plants Collection

Germination requirements: Groundcover Plants Collection

Armeria maritima (thrift)

  • Sow seeds directly where they are to grow in spring or autumn
  • Before sowing, soak the seeds in warm water overnight
  • Lightly cover the seeds with compost
  • Keep at 15–20°C
  • Germination can take 30–90 days

Haplocarpha scaposa (false gerbera)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 18–20°C
  • Germination should occur within 30–90 days

Erigeron karvinskianus (Mexican fleabane)

  • Sow seeds and leave them uncovered, as they need light to germinate
  • Keep at 15–20°C
  • Germination should occur within 30 days
  • Plants can self-seed freely once established

Luzula nivea (snow rush)

  • Sow seeds in spring or autumn
  • Lightly cover the seeds with compost
  • Keep at 15–20°C
  • Germination can take up to 90 days

Phalaris canariensis (birdseed grass)

  • Sow seeds directly where they are to grow in spring
  • Lightly cover the seeds with soil
  • Keep at 20°C
  • Germination can be slow and uneven, taking 2–12 weeks

Rock Garden Plants Collection

Germination requirements: Rock Garden Plants Collection

Dicentra formosa (western bleeding heart)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 10–16°C
  • Germination can take up to one year

Eranthis hyemalis (winter aconite)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 5–12°C
  • Germination can be slow and uneven
  • Germination should occur within 90 days

Muscari armeniacum (Armenian grape hyacinth)

  • Sow seeds in autumn
  • Before sowing, soak the seeds in cold water
  • Lightly cover the seeds with grit
  • Sow into a suitable container, as the plant dislikes root disturbance
  • Keep at 10–15°C
  • Germination can take up to one year

Penstemon hirsutus (hairy penstemon)

  • Sow seeds in autumn or early spring
  • Lightly cover the seeds with fine gravel or compost
  • Keep the soil surface moist
  • Keep at 20°C
  • Germination can take up to 90 days

Pulsatilla vulgaris (pasqueflower)

  • Lightly cover the seeds with compost
  • Seeds require a period of cold, moist stratification
  • Keep at 13–16°C
  • Germination can take up to one year

Specialist picks

Carefully selected collections for challenging conditions and specialist growing situation

Plants for Clay Soils Collection

Germination requirements: Plants for Clay Soils Collection

Chelone obliqua (twisted shell flower)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Use a well-drained seed compost
  • Keep at 15°C
  • Germination should occur within 90 days

Digitalis grandiflora (large yellow foxglove)

  • Sow seeds in late spring
  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 15°C
  • Germination can take 30–90 days

Lysimachia ephemerum (willow-leaved loosestrife)

  • Sow seeds in spring or autumn
  • Cover the seeds with a thin layer of gravel
  • Seeds require a period of cold, moist stratification
  • Keep at 13–18°C
  • Germination can be slow and uneven
  • Germination can take up to 90 days

Primula pulverulenta (mealy primrose)

  • Sow seeds and leave them uncovered, as they need light to germinate
  • Seeds require a period of cold, moist stratification
  • Keep at 13–16°C
  • Germination can take up to 90 days

Veronicastrum virginicum (Culver’s root)

  • Surface-sow the seeds and do not cover them, as they need light to germinate
  • Keep at 16–21°C
  • Germination can take up to 90 days

Plants for Chalk Soils Collection

Germination requirements: Plants for Chalk Soils Collection

Adenophora bulleyana (Bully’s ladybells)

  • Sow seeds in autumn
  • Avoid disturbing seedlings, as the plant resents root disturbance
  • A period of cold treatment may improve germination
  • Keep at 10–13°C
  • Germination can take 30–90 days

Malva moschata (musk mallow)

  • Sow seeds in early summer
  • Lightly cover the seeds with compost
  • Keep at 16–21°C
  • Germination can take up to 90 days

Scabiosa columbaria (small scabious)

  • Sow seeds in autumn
  • Lightly cover the seeds with compost
  • Keep at 16–21°C
  • Germination can be slow and uneven
  • Germination can take up to 90 days

Silene uniflora (sea campion)

  • Sow seeds directly where they are to grow in spring or autumn
  • Lightly cover the seeds with soil
  • Keep at 16–21°C
  • Germination should occur within 30 days

Verbascum chaixii ‘Album’ (white nettle-leaved mullein)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 15–18°C
  • Germination should occur within 30 days

Plants for Acid Soils Collection

Germination requirements: Plants for Acid Soils Collection

Callistemon subulatus (dwarf bottlebrush)

  • Sow seeds and leave them uncovered, as they need light to germinate
  • Keep at 16–21°C
  • Germination can take more than 90 days

Enkianthus campanulatus (redvein enkianthus)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 13–16°C
  • Germination should occur within 30–90 days

Gillenia trifoliata (Bowman’s root)

  • Sow seeds in autumn
  • Seeds require a period of cold, moist stratification
  • Keep at 15–18°C
  • Germination should occur within 30–90 days

Lupinus angustifolius (narrow-leaved lupin)

  • Before sowing, soak the seeds in hot water for 1–3 days or carefully chip the seed coat
  • Sow the seeds and cover with 5mm of compost
  • Keep at 13–18°C
  • Germination can take up to 90 days

Molinia caerulea subsp. caerulea (purple moor-grass)

  • Sow seeds in autumn
  • Lightly cover the seeds with compost
  • Seeds require a period of cold, moist stratification
  • Keep at 10–15°C
  • Germination should occur within six months

Plants for Windswept/Exposed Sites Collection

Germination requirements: Plants for Windswept/Exposed Sites Collection

Eragrostis curvula (African love grass)

  • Surface-sow the seeds and do not cover them
  • Keep the compost moist and maintain high humidity
  • Keep at 20–22°C
  • Germination should occur within 30 days

Phlomis russeliana (Turkish sage)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 13–18°C
  • Germination can take up to six months

Salvia nemorosa (Balkan clary)

  • Sow seeds in spring
  • Leave the seeds uncovered when sowing
  • Keep at 18–24°C
  • Germination should occur within 30 days

Sporobolus heterolepis (prairie dropseed)

  • Sow seeds indoors from autumn to early spring
  • Keep at 15–20°C
  • Germination should occur within 30 days

Stachys byzantina (lamb’s ear)

  • Sow seeds in spring
  • Lightly cover the seeds with compost
  • Keep at 18–21°C
  • Germination can take 30–90 days

Handy tools and information

Need a little more help? Find advice, suppport and ways to track your seeds, right at your fingertips

Get in touch

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