Shasta daisies (Leucanthemum × superbum) are the classic white-petaled, yellow-centered perennial that most people picture when they hear the word "daisy." A member of the aster family, this clump-forming perennial is sturdy, long-lived, and about as straightforward as perennials get, which makes it a good choice for a beginning gardener or anyone who wants reliable results without much fuss. Plants bloom in a strong flush in early-to-mid summer, and deadheading can coax out a second round of flowers later in the season. Shasta daisies are fully hardy throughout Kentucky and one of the most dependable sources of classic white cut flowers for a home cutting garden.
Sowing and planting
Shasta daisies are typically planted as potted perennials rather than started from seed, since named cultivars don't always come true from seed and nursery plants establish and bloom faster. If you do want to start from seed, sow indoors 6 to 8 weeks before the last frost date, pressing seed lightly into the surface since it needs light to germinate; seed-grown plants may not flower heavily until their second year.
Plant out container-grown Shasta daisies in spring after the last frost, or in early fall at least 6 weeks before the first hard freeze to give roots time to establish before winter. Choose a site in full sun; plants tolerate a little afternoon shade in hot weather but bloom best and stay sturdiest with a full day of sun. Space plants 18 inches (45 cm) apart, since clumps widen steadily over a few seasons and need room to expand without crowding. Dig a hole about the size of the root ball, set the crown level with the surrounding soil, backfill, and water in thoroughly. Shasta daisies aren't particular about soil fertility but do need good drainage; amend heavy clay with compost at planting time if water tends to stand on the site.
Growing on
Water regularly through the first growing season while roots establish, then taper off; established clumps handle normal rainfall in most Kentucky summers and only need supplemental watering during extended dry spells. Good drainage matters more than rich soil, especially over winter, since soggy soil around the crown is a more common problem than drought. A light application of balanced fertilizer in spring is enough; heavy feeding produces excess leafy growth and weaker stems without improving bloom.
Taller cultivars can flop in open, windy sites or after heavy rain, so staking with twiggy brush or a peony ring in late spring, before plants fill out, keeps the clump looking tidy without being obvious once the foliage grows up and around it. Deadhead spent blooms throughout the season by snipping the flower stem back to a set of leaves or a side bud; this tidies up the plant's appearance, since a Shasta daisy clump left uncut looks ragged and brown once the first flush of bloom fades, and it often prompts a second, lighter flush of flowers later in summer. Divide clumps every 2 to 3 years in spring or fall. Division keeps plants vigorous, since the center of an older clump tends to die out and thin while the outer edges keep growing, and it's also the easiest way to multiply your planting for free: lift the clump, pull or cut it into sections with healthy roots and shoots, and replant the vigorous divisions while discarding the worn-out center.
Harvesting
Shasta daisies are one of the best cut flowers in a Kentucky perennial border, with sturdy stems and a clean white-and-yellow look that pairs with almost anything else in a bouquet. Cut stems in the cool of morning, choosing flowers that are fully open or just opening, and cut back to a good length just above a leaf node or side bud to encourage more stems to follow. Place cut stems in water promptly, recut the ends at an angle, and change the water every couple of days; cut Shasta daisies typically hold up well in a vase for a week or more.
Whether or not you cut for arrangements, deadhead spent blooms regularly through the growing season. Removing faded flowers prevents the plant from putting energy into seed production, keeps the clump looking neat instead of brown and ragged, and is usually what triggers a second, lighter bloom flush later in summer.
Problems and pests
Leaf spot in humid weather
Fungal leaf spot shows up as small brown or black spots on the foliage during warm, humid stretches, particularly when plants are crowded or watered overhead in the evening. It's mostly cosmetic on an otherwise healthy clump. Water at the base rather than over the foliage, space plants to allow airflow, and remove badly spotted leaves to limit spread.
Aphids on buds and new growth
Aphids sometimes gather on flower buds and tender new shoots in spring, feeding on sap and occasionally distorting new growth. Beneficial insects like ladybugs usually bring light populations under control on their own. A strong blast of water from the hose, repeated every few days, or insecticidal soap handles a heavier infestation.
Powdery mildew on foliage
A white, powdery coating on leaves can appear during still, humid weather, especially late in the season. It rarely threatens an established plant but detracts from its appearance. Thin crowded clumps by dividing them on schedule, and water the soil rather than the leaves to keep foliage drier.
Dying, hollow centers in established clumps
Clumps that have been in place for several years without division often die out in the middle, leaving a ring of healthy growth around a bare or woody center. This is a normal aging pattern rather than a pest or disease problem. Divide the clump in spring or fall, discard the old center, and replant the vigorous outer sections to restore a full, even clump.
Crown rot in poorly drained soil
Shasta daisies are more likely to suffer from soggy, poorly drained soil than from dry conditions, particularly over a wet winter. Affected plants may wilt or fail to resprout in spring despite looking healthy the previous fall. Plant in a well-drained site to begin with, and avoid mulching heavily right up against the crown, which traps moisture against it.
Varieties worth growing
- Becky – A tall, sturdy cultivar with large flowers and strong stems that hold up well without staking in most sites; a popular choice for cutting gardens.
- Snowcap – A compact, early-blooming cultivar that stays shorter and tidier than taller types, suited to the front of a border.
- Alaska – An older, widely available cultivar with classic single white flowers and good cold hardiness.
- Crazy Daisy – A novelty cultivar with shaggy, informal double and semi-double flowers instead of the classic simple daisy form.
- Silver Princess – A dwarf cultivar that stays especially compact, good for edging or smaller garden spaces.
- Real Glory – Semi-double flowers with extra petals for a fuller-looking bloom than single-flowered types.