Small bulbs to naturalize: winter aconite, squill, snowdrop and company

Small naturalising bulbs are those that grow to 10–50 cm tall and, once planted in autumn, multiply on their own and return each year: winter aconite (Eranthis hyemalis), Siberian squill (Scilla siberica), chionodoxa, snowdrop (Leucojum), wood hyacinth (Hyacinthoides non-scripta), snake’s head fritillary (Fritillaria meleagris), reticulated iris (Iris reticulata) and hardy cyclamen.

This guide presents them genus by genus, with their RHS hardiness rating, and tells you which to choose for your soil: cool woodland, dry shade, moist soil or sunny, well-drained earth.

The general principles of naturalising are in our guide to bulbs that return every year, and our bulbs to plant in autumn are gathered in a collection.

🌟 Why choose small bulbs for naturalising

Small bulbs are the best candidates for naturalising because they are quick to plant, can be planted in large numbers, and thrive where large border bulbs fail: under deciduous trees, in short grass or in a damp meadow.

The RHS guide to naturalising bulbs in grass lists squill, chionodoxa, reticulated iris, winter aconite and snowdrop among the bulbs to naturalise in grass, alongside crocuses and snowdrops. They flower early, often before the trees cast shade, and their foliage then disappears without causing problems.

Several are also very hardy: the RHS rates summer snowdrop and reticulated iris H7, below -20 °C.

📊 Small bulbs for naturalising: the genus-by-genus table

To choose a small bulb, cross-reference its preferred soil with its hardiness: all those in this table can survive winter in the ground, but not in the same soils. Hardiness ratings, soils and heights come from RHS fact sheets, unless stated otherwise.

On the RHS hardiness scale (Royal Horticultural Society), H5 corresponds to -15 to -10 °C, H6 to -20 to -15 °C and H7 to minimum temperatures below -20 °C.

📋 Quick fact sheet

Common features of small bulbs for naturalising, according to the RHS and NC State Extension.

🪏 How to naturalise small bulbs, step by step

To naturalise small bulbs, plant them in autumn by the dozen, at about three times their height, scattered as they would grow in nature, then leave them be without mowing too early.

🧭 Which small bulbs for your soil: woodland, dry shade, moist or well-drained

The right small bulb depends first on your soil and the light in spring: some like the coolness of woodland, others the moisture of a meadow, and others well-drained earth in the sun. Here is the selection for each situation, according to the RHS, NC State Extension and INPN.

🔑 Wood hyacinth: native or Spanish?

The true wood hyacinth is Hyacinthoides non-scripta, native to Western Europe, including France (Belgium, France, Great Britain, Ireland, the Netherlands, Portugal, Spain), according to POWO (Kew); Spanish wood hyacinth, Hyacinthoides hispanica, resembles it but hybridises with it and produces Hyacinthoides × massartiana.

According to the RHS page on wood hyacinths in gardens, the native species has dark blue-purple, scented flowers with recurved petals arranged on one side of an arching stem, with leaves about 1.5 cm wide.

The Spanish wood hyacinth has larger, paler blue, unscented flowers arranged all around an upright stem, and leaves about 3 cm wide. The RHS advises that if your garden is near a wild population, you should plant neither the Spanish wood hyacinth nor the hybrid, to prevent pollinators from carrying their pollen.

The RHS Hyacinthoides hispanica fact sheet states that it is classified as an invasive non-native species in Northern Ireland. Both are rated H6: reserve the Spanish wood hyacinth for town gardens, away from woodland.

💡 Squill and chionodoxa: the small blue bulbs

Squill and chionodoxa are two very similar small blue bulbs, so much so that botanists have grouped them together: POWO (Plants of the World Online, Kew) treats Chionodoxa luciliae as a synonym of Scilla luciliae.

In practice, Siberian squill (Scilla siberica) has small bright blue bells nodding towards the ground, in clusters of 2–5, while chionodoxa, now sold under the name Scilla forbesii, opens blue star-shaped flowers with white centres facing the sky. The RHS rates both H6 and grows them in sun or partial shade, in well-drained soil.

Plant them in large patches under deciduous shrubs or in short grass: they multiply year after year. For bulbs that benefit pollinators, see our guide to pollinator-friendly bulbs.

❄️ Winter aconite, snowdrop and snake’s head fritillary: late winter and damp meadows

Winter aconite opens the season in late winter, with snowdrop and snake’s head fritillary taking over in spring, the former in woodland and the other two in cool to damp soils.

According to the NC State Extension fact sheet, winter aconite is planted in late summer or early autumn, 5–7.5 cm deep and 7.5 cm apart, in rich, well-drained soil, preferably alkaline, kept cool during growth.

The summer snowflake (Leucojum aestivum) actually blooms in mid-spring; NC State says it tolerates wet and clay soils and should be planted at a depth of 5 to 10 cm. The striped fritillary grows wild in the wet meadows of alluvial valleys and, according to the INPN, is protected in many regions: never pick it in the wild, buy cultivated bulbs instead.

The RHS also recommends the spring snowflake (Leucojum vernum) for naturalizing in lawns.

🍃 Hardy cyclamens and dwarf irises: small bulbs for well-drained soils

The Naples primrose, the coum, and the dwarf iris are small bulbs for well-drained soils: cyclamens in partial shade under trees, irises in full sun. The Naples primrose (Cyclamen hederifolium) blooms in early autumn before its leaves appear and self-sows freely; the coum (Cyclamen coum) blooms in the middle of winter, from January to March, according to the RHS.

Plant their tubers at only 3 to 5 cm deep in humus-rich, well-drained soil without excess moisture in summer: if planted too deeply, they may not flower. The reticulata iris, rated H7, needs well-drained, neutral to slightly alkaline soil in full sun; NC State Extension says it flowers from March and recommends planting the bulb about 12 cm deep to its base.

According to the ASPCA (American Society for the Prevention of Cruelty to Animals) cyclamen fact sheet, Cyclamen spp. is Toxic to Dogs, Toxic to Cats, Toxic to Horses. The ASPCA also classifies Iris species as « Toxic to Dogs, Toxic to Cats, Toxic to Horses ».

For the other genera, the RHS states « not to be eaten » for Siberian squill, winter aconite, summer snowflake, and fritillary, and « Harmful if eaten » for dwarf iris, winter aconite, and wood hyacinth: wear gloves and keep the bulbs out of reach of animals.

For other cool-season flowers, see our guide to winter flowers.

🗓️ Small bulbs naturalized throughout the seasons

Once established, small bulbs require almost nothing: plant them in autumn, do not water them once they are in the ground, and above all, be patient when mowing. The RHS recommends waiting at least six weeks after flowering, ideally until the foliage is yellow and dry, before mowing.

For more details on what to do after flowering, see our page what to do with bulbs after flowering.

📅 Seasonal maintenance calendar

🐛 Mistakes to avoid with small bulbs for naturalizing

Small bulbs that do not return have almost always been mown too early, planted in the wrong soil, or planted too deeply.

🌿 Our small bulbs for naturalizing and their fact sheets

Our small bulbs are planted in autumn and are grouped in our collection of bulbs to plant in autumn.

🌷 Small bulbs and large bulbs: where naturalizing ends

Not all bulbs naturalize as well as the small genera in this guide. Daffodils, alliums, and botanical tulips readily return, while large hybrid tulips often become exhausted after a few years: our guide to bulbs that return every year makes the distinction.

To create a border rather than a carpet, see our bulbs to plant in autumn; for the planting depth rules for all bulbs, see our page when and how to plant bulbs.

And for summer, summer bulbs take over in spring.

✅ Our tips for succeeding with small bulbs for naturalizing

To succeed with small bulbs for naturalizing, choose the genus according to your soil, plant it in autumn in large numbers and scatter them, then let the foliage yellow before mowing. In a few years, winter aconites, squills, snowflakes, and wood hyacinths form carpets that return on their own.

Find our bulbs to plant in autumn and our shade and cool plants.