Heather N. Kolich, ANR Agent, UGA Extension Forsyth County

Dark mornings and evenings and colder temperatures at night let us know that winter is on the way. It may seem paradoxical, but October to December is the time to plant spring-flowering bulbs. That’s because most types of spring-flowering bulbs need 3-4 months of cold to stimulate those cheerful flowers to bloom.

Where to plant spring-flowering bulbs

Bulbs tolerate a range of soil conditions, and spring flowers brighten up the regular full-sun focal spots, like dooryards, flower beds, and that area around the mailbox. But early blooming spring bulbs can add pops of colorful beauty to wooded spaces, as well. Locate these bulbs where they can soak up full sunshine while the surrounding trees are dormant and leafless.

Layering bulbs for waves of blooms

The term “bulb” includes true bulbs as well as perennial producers such as corms, tubers, tuberous roots, and rhizomes. Spring-flowering bulbs bloom in a wide variety of colors, shapes, and heights across the spring season. Bulbs are planted at different depths, depending on size and type. By layering bulbs vertically in the planting, we can get weeks of changing colors and blooms, even small gardens and planters.

Eight purple crocus flowers in bloom.
Cheerful crocus are among the earliest flowering spring bulbs. Photo by Yoksel Zok on Unsplash.

To create a layered – or lasagna – garden, select a variety of small and large bulbs; early, mid, and late season bloomers; tall and short growers; and complementary colors. (See the chart below for guidance.) Dig the planting area down to 6-inches, or the planting depth for the deepest bulbs. Place the deepest-planted bulbs in the desired arrangement, keeping root ends pointed down and shorter bloomers forward of taller bloomers. Cover the area with 1-2 inches of soil and arrange the mid-depth bulbs, then cover them with 1-2 inches of soil and place the shallow layer bulbs. Add the final layer of soil and place rhizomes just below the soil surface.

While some bulbs will naturalize or spread over time, others, including tulips and hyacinths (Hyacinthus orientalis) decline and may fail to bloom after a year or two. Fall is the time to dig up crowded bulbs and divide them to share or replant elsewhere.

Forsyth County Extension is hosting an on-line, spring bulb fundraising event, featuring many wonderful flowering and foliage bulbs for fall planting and layered gardens. Order online at https://store.giveandgarden.com/pages/fundraiser/forsyth-county-extension-forsyth-county-extension-fundraiser. Proceeds from purchases will support Forsyth County Extension Master Gardener and Master Naturalist volunteer outreach projects and programs.

Chart 1. Selection Guide for Layering Spring-flowering Bulbs

Common NameBotanical NameType/ Planting DepthFlowering HeightFlower Color
Very Early Bloomers
CrocusCrocusCorm/  2”4”White, Yellow, Purple
Winter AconiteEranthus hyemalisTuber/  2”4”Yellow
Iris – bulbousIris danfordiae, I. reticulataBulb/ 2”5-6”Violet to purple with white and yellow markings
Early Bloomers
Anemone, Greek WindflowerAnemone blandaTuber/ 2”6”Blue, red, white, pink
Glory of the SnowChionodoxa luciliaeSmall bulb/ 2”5”Blue, white
SnowdropsGalanthus nivalisSmall bulb/ 2”6”White
Grape HyacinthMuscari botryoidesSmall bulb/ 3”5”Purple, white
Siberian SquillScilla sibericaSmall bulb/ 3”4”Blue, white
Midseason Bloomers
Crown ImperialFritillaria imperialisLarge bulb/ 6”3’Yellow, Orange, Red, Burgundy
HyacinthHyacinthus orientalisLarge bulb/ 4”10”Many
Spring StarflowerIpheion uniflorumBulb/ 3”6”White, blue, purple, pink
Narcissus, Daffodil, JonquilNarcissus species & hybridsSmall to large bulbs/ 3”-6” Early-mid season6-24”White, Yellow
Rain LilyZephryanthes species & hybridsSmall bulb/ 2”6-8”White, Yellow, Pink
Late Season Bloomers
Lily of the ValleyConvallaria majalisRhizome/ just below soil surface8”White
Spanish BluebellEndymion hispanicusBulb/ 3”8”Blue
Iris – rhizomatousIris siberica, I. kaempferiRhizome/ just below soil surface3’Many
TulipTulipa species & hybridsBulb/ 4”-6”3-30”Many
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