Bulbs in the Garden: Spring, Summer & Fall Planting

The most recognised spring bulb, available in virtually every colour except true blue. Tulips are divided into 15 division groups by flower form and bloom time — from single early tulips in March through late-blooming parrot and viridiflora types in May. Plant 6–8 inches deep in groups of 9 or more for visual impact. Tulips perform strongest in their first year; replanting every 3 years maintains peak performance in most zones. In zones 8–10, treat as annuals or pre-chill. Excellent for cut flowers.

The most dependable spring bulb for long-term naturalising. Unlike tulips, daffodils are deer-resistant (the alkaloid lycorine is toxic to most mammals), multiply readily, and return stronger each year without lifting. Bloom times span from February (early varieties like 'February Gold') through May (late varieties like 'Thalia' and 'Cheerfulness'). Plant 6–8 inches deep. Mix early, mid-season, and late varieties for 8–10 weeks of continuous daffodil bloom. Requires well-drained soil — bulbs rot in waterlogged conditions.

Among the earliest garden flowers, crocuses bridge late winter and early spring. Species crocuses (Crocus tommasinianus, C. chrysanthus) bloom 2–3 weeks before Dutch hybrid crocuses and naturalise more freely. Plant 3 inches deep in large drifts — 50 or more corms for a convincing naturalistic effect. Crocuses are the first significant nectar and pollen source for early-emerging bees and bumblebees emerging from dormancy. Squirrel predation is common in areas with high populations; plant under a layer of chicken wire or use bone-meal-free fertiliser.

Hyacinths deliver the most powerful fragrance of any spring bulb. A single spike perfumes a 10-foot radius. Plant 5–6 inches deep in groups of 5–7. Hyacinths are shorter-lived than daffodils — the dense flower spike degrades to a looser, more relaxed form from the second year onward, which many gardeners find more natural. Wear gloves when handling — the bulb skin is mildly irritating to sensitive skin. Excellent for forcing indoors in winter.

Alliums are the architectural bulbs of the late-spring garden. Giant allium (A. giganteum) produces 4–6 inch spherical purple flower heads on 3–4 foot stems. Allium 'Purple Sensation' is more compact at 24 inches and highly reliable. Plant 6–8 inches deep. Allium foliage dies back before the flowers open, so position them behind lower-growing plants. The dried seed heads remain decorative through summer and are outstanding in flower arrangements. Deer and rodent resistant.

Muscari are small, inexpensive, and extraordinarily prolific. The 6-inch cobalt-blue flower spikes bloom in April alongside mid-season tulips and daffodils, providing the blue tones that most spring gardens lack. Plant 3 inches deep in large masses — 100+ bulbs for a river-of-blue effect. Muscari naturalise aggressively and will spread across a bed over 3–5 years. Use this as a feature, not a problem: they create a reliable carpet that requires no replanting. The foliage appears in autumn, well before the flowers, providing winter greenery.

Snowdrops are often the first flowers of the calendar year, blooming through snow cover as early as late January in zone 7. The pendant white flowers are modest in size but extraordinary in their timing. Plant 3 inches deep in informal drifts beneath deciduous trees and shrubs. Snowdrops prefer humus-rich, consistently moist soil — they do not tolerate summer drought. They are best planted "in the green" (as growing plants with foliage attached, available March–April) rather than as dry bulbs, which have low survival rates. Once established, they naturalise reliably and require no attention.

The most productive and diverse summer bulb in cultivation, with over 50,000 registered varieties spanning plate-sized dinner plate types (12+ inches across) to compact pompoms (2 inches). Dahlias bloom continuously from mid-July through first hard frost — the longest bloom window of any tender bulb. Plant tubers 4–6 inches deep after last frost, eyes facing upward. Stake tall varieties (over 3 feet) at planting to avoid root disturbance later. Deadhead spent flowers every 2–3 days to maintain continuous bloom. In zones 8+, tubers can overwinter in the ground with mulch. In zones 3–7, lift after first frost, dry for 1–2 weeks, and store in dry peat at 45–50°F.

Gladiolus corms produce tall (3–4 foot) flower spikes with 20–30 florets opening sequentially from bottom to top, extending the bloom window on each stem for 10–14 days. For continuous supply, succession-plant corms every 2 weeks from April through June. Plant 4–6 inches deep in groups of 10+ for visual mass. Gladiolus are outstanding cut flowers — cut spikes when the bottom 2–3 florets begin to open. Corms are tender (hardy to zone 8 in the ground) and must be lifted before frost in most of the country. Hardy gladiolus (Gladiolus communis byzantinus) is an exception — fully hardy to zone 5 and self-seeds freely.

Cannas are tropical plants that deliver bold foliage (green, purple-bronze, or variegated) alongside vivid flowers in red, orange, yellow, pink, and bicolours. They grow rapidly from rhizomes to 4–8 feet in a single season, making them the most impactful quick-fill plant in the summer garden. Plant rhizomes 4 inches deep after last frost. In zones 8–11, cannas are perennial and can stay in the ground year-round. In zones 7 and colder, lift rhizomes before frost, divide, and store like dahlias. Cannas require consistent moisture and perform exceptionally well in rain gardens and at pond edges.

Crocosmia produces arching sprays of fiery orange-red or yellow flowers on 24–36 inch stems, with fine upright foliage that provides structure before and after bloom. 'Lucifer' is the classic variety — scarlet red, vigorous, and fully hardy to zone 5 (the hardiest of all summer corms). Plant corms 3–4 inches deep after last frost in groups. Crocosmia spreads by cormlets and self-seeds lightly; divide clumps every 3–4 years. Outstanding for wildlife — the tubular flowers are a key food source for hummingbirds. Fresh stems last 2 weeks as cut flowers. For more options pairing with crocosmia, see our cottage garden plants guide.

Caladiums are grown for their spectacular tropical foliage rather than flowers — heart-shaped leaves in combinations of white, pink, red, and green provide a colour display that rivals any flower. They are among the best shade-tolerant tubers available, performing in dappled light to deep shade where most summer bulbs fail. Plant tubers 2 inches deep after soil warms to 70°F. Caladiums require consistent moisture and well-drained soil rich in organic matter. In all but the warmest zones, lift before first frost and store at 60°F minimum over winter.

Tuberous begonias are the premier shade-tolerant summer bulb, producing camellia-like flowers 3–6 inches across in shades of red, orange, yellow, pink, and white. They are outstanding in containers and hanging baskets. Start tubers indoors 6–8 weeks before last frost, concave side up, barely covered with moist compost. Tubers are sensitive to overwatering — allow the top inch of soil to dry between waterings. Lift before frost and store like dahlias. In zones 9–11, tubers can remain in containers year-round.

Colchicum are often called autumn crocus, though they are unrelated to true crocuses (genus Crocus). The large pink, lilac, or white goblet-shaped flowers emerge directly from bare soil in September–October without any foliage. Plant corms 4 inches deep in July–August. The strap-like foliage appears the following spring, grows vigorously for 6–8 weeks, then dies back by June — a pattern worth accounting for in bed design. All parts of the plant are toxic (colchicine is used medicinally as a gout treatment). Hardy to zone 4 and fully perennial once established.

Lycoris earns its common name "surprise lily" because the flowers appear suddenly from bare ground in late August with no preceding foliage — the stems emerge and bloom within days. Lycoris squamigera (magic lily) produces clusters of pink, strap-petalled flowers on 18-inch stems and is hardy to zone 5. Lycoris radiata (red spider lily) is more tender (zone 7) but more striking, with vivid red reflexed petals and prominent stamens. Plant bulbs 4–6 inches deep in July. Foliage appears in spring and dies back by June. These bulbs strongly dislike disturbance — plant in a permanent location and leave undivided for several years.

Nerines produce clusters of strap-petalled flowers in shades of pink, red, and white on 18–24 inch stems in September–November. Nerine bowdenii is the most reliably hardy species, surviving to zone 6 in well-drained soil against a south-facing wall. Most other nerine species are tender to zones 8–10. Plant bulbs with their necks at or just above soil surface — do not bury them. Nerines are long-lived cut flowers (2–3 weeks in a vase) and bloom more freely when potbound, making them excellent container plants for zones 5–7 where they can be overwintered indoors.

Cyclamen coum is a small woodland tuber that flowers in autumn and persists through winter into early spring, often blooming through snow in zones 5–7. The reflexed pink or white flowers rise above beautifully marbled silver-green foliage. Plant tubers 1–2 inches deep (shallower than most bulbs) in humus-rich, well-drained soil in partial to full shade. Once established, cyclamen are very long-lived and self-seed freely to create natural colonies beneath trees and shrubs. They thrive in dry summer conditions (unlike most bulbs) and are ideal for planting under deciduous trees where summer rain is limited by the canopy.