What’s in Bloom?

This page offers bloom updates for popular trees and shrubs in Longenecker Horticultural Gardens and native plants in the Wisconsin Native Plant Garden and natural areas.

Notes for visitors:

Longenecker Horticultural Gardens

2025 weekly bloom updates

May 21:

Although the lilac collection has passed peak bloom, there are still excellent quality blossoms on display throughout the collection. Given the current weather forecast, these should persist into next week.

The azalea collection is in full bloom and expected to last into the weekend.

Buckeye and horse chestnuts are in peak bloom and expected to be in prime form through the weekend.

Most magnolias are done for the season, but the North American native cucumber-tree and umbrella-tree magnolias, along with the Asian Oyama magnolia, are in full bloom and expected to last through the weekend.

Although most of the crabapple collection is done blooming, the Wisconsin native prairie crabapple and its cultivars are in full bloom and expected to last into the weekend.

The catalpa collection is just starting to bloom, with many specimens expected to flower over the next week.

Also in bloom: Aronia, beautybush, daphne, deutzia, dogwood, hawthorn, mountain-ash, pawpaw, roses, spiraea, weigela.

May 12:

While most magnolias are done blooming for the season, about a dozen plants still have excellent floral displays.

The lilac collection is in peak bloom, which is expected to last through the week. Please note that the lilac collection is composed of early, mid, and late flowering selections. This prolongs the bloom season but also means that the collection is never completely in bloom.

The crabapple collection is just beyond peak bloom, but there are still exceptional flower displays throughout the collection.

Buckeye and horsechestnuts have started to bloom, with about ten trees in full bloom and many more expected to come into flower through the week.

Also in bloom: Aronia, azalea, daphne, fothergilla, flowering quince, mountain-ash, ash, pawpaw, pearlbush, redbuds, roses, rhododendrons, silverbells, early flowering spiraeas, weigela.

May 6:

While the peak flowering period has passed, there are still over twenty magnolias with good to excellent flower displays.

Most flowering cherries are done, though a few specimens still have excellent floral displays.

Around thirty percent of our lilac collection is in bloom, with additional flowering expected to accelerate throughout the week in response to warm temperatures. Currently, peak bloom is expected to begin over the weekend. Please note that the lilac collection is composed of early, mid-, and late-flowering selections. This prolongs the bloom season but means that the collection is never completely in bloom.

Over half of our crabapple collection is in bloom, with peak bloom expected to begin later this week into the weekend.

Buckeye and horsechestnuts are just coming into bloom.

Also in bloom: Daffodils, fothergilla, flowering pears, flowering quince, flowering almonds, pearlbush, redbuds, early flowering rhododendrons, early flowering spiraeas, Korean spice viburnums, and wild plums.

April 30:

More than fifty magnolias are in bloom. While most of the earliest blooming types are finished or fading, mid-season bloomers are in full flower, including the “Girl” series. Later blooming types, including yellow-flowering forms and Ledvina hybrids, are just coming into bloom.

The flowering cherry collection is at the end of its bloom cycle, with a few specimens still showing outstanding color.

Around forty early flowering lilac types are beginning to bloom, with many more expected by the middle of next week. It is too early to predict peak bloom times.

Over thirty-five crabapples are in bloom, with peak bloom expected by late next week.

Also in bloom: Amelanchier species, daffodils, flowering pears, flowering quince, flowering almonds, pearlbush, redbuds, early flowering rhododendrons, early flowering spiraeas, Korean spice viburnums, and wild plums.

April 24:

More than fifty magnolias are in bloom, with an additional forty more still to come. While some of the earliest blooming types are just beginning to fade, many mid-season bloomers are just coming into full flower, including the “Girl” series and several yellow-flowering types.

About half of our flowering cherry collection is in full bloom, with additional specimens expected to come into bloom over the weekend.

A handful of early flowering lilac types are just coming into bloom. It is too early to predict peak bloom times.

Our first crabapple is coming into bloom with more expected over the weekend.

Also in bloom: Amelanchier species, daffodils, cornelian-cherry dogwood, flowering pears, flowering quince, flowering almonds, forsythia, redbud and early flowering rhododendrons.

April 18:

While no flowering plants were damaged on Wednesday morning when temperatures dipped below freezing, cool and cloudy days have slowed blooming.

More than twenty-five of the earliest flowering magnolia types are in full bloom. An additional handful of mid-season bloomers are just coming into flower.

A handful of flowering cherries are in full bloom, with additional specimens just coming into bloom. Given the current weather forecast, peak flowering is expected to start later next week.

Lilac bud swelling has begun on early flowering types. A few blooms are expected to open late next week. It is too early to predict peak bloom times.

Crabapple buds have begun swelling. Flowering is not expected to begin before late next week.

Also in bloom: Flowering pears, Cornelian-cherry dogwood, forsythia, red and Freeman maples, vernal witchhazel, early viburnum types.

April 14:

More than twenty-five of the earliest flowering magnolia types are showing significant color, with a handful already in full bloom and others expected to be in full bloom later in the week. Freezing temperatures are forecast for Wednesday morning. Depending on the degree and length of cold, some open flowers may be significantly damaged.

A few flowering cherry blooms have begun to open with additional flowering expected to accelerate through the week. Given the current weather forecast, peak flowering is expected to start this weekend.

Lilac bud swelling has begun on early flowering types. First blooms are expected over the weekend. It is too early to predict peak bloom times.

Crabapple buds have begun swelling. Some flowers are expected to open by the weekend.

Also in bloom: Cornelian-cherry dogwood, forsythia and white forsythia, red and Freeman maples, vernal witchhazel, early viburnum types.

April 7:

Blossoms on a few magnolias have begun to open. All varieties have some minor frost damage to older flowers. Bloom timing and progression is weather dependent. Cool temperatures slow blooming, and warm temperatures will accelerate it. While the fuzzy outer bud scales protect closed buds, freezing temperatures can damage open flowers.

Forsythia are in full bloom. Cornelian-cherry dogwoods are nearing full bloom. Lilac buds are beginning to emerge. Cherry buds are swollen, none are blooming. Crabapple buds are beginning to open, none are blooming.

Bloom time ranges

Time ranges are estimates. Actual bloom dates depend on weather conditions and will be noted in bold when buds begin to open. This date does not reflect peak bloom.

  • Cherries (Prunus spp.): early to mid-April /April 14
    44 specimens (consisting of 21 taxa*)
  • Magnolias (Magnolia spp.): April–May / April 3
    110 specimens (consisting of 75 taxa)
  • Crabapples (Malus spp.): April–May
    200 specimens (consisting of 150 taxa)
  • Lilacs (Syringa spp.): April–May
    400 specimens (consisting of 260 taxa)
  • Rhododendrons and azaleas (Rhododendron spp.): mid-April–May
    99 specimens (consisting of 65 taxa)
  • Horsechestnut/Buckeyes (Aesculus spp.): mid-May
    31 specimens (consisting of 24 taxa)

*taxa include species, subspecies, and cultivars

About blooming tree collections

Collections include early, mid-, and late-flowering types, and there is a range of bloom times within any particular collection. Bloom timing and duration are affected by weather. Hot sunny days may cause early flowering but can decrease bloom length. Cool cloudy days can delay flowering but lengthen bloom period. Open flowers are easily damaged by freezing temperatures.

Wisconsin Native Plant Garden

Bloom Updates

Native plants will generally bloom earlier in the gardens than they do in the natural areas. First bloom date is in the Native Plant Garden unless otherwise noted.

  • Toothwort (Cardamine concatenata): April–May
  • Trout-lily (Erythronium spp.): April–May
  • Hepatica (Anemone acutiloba): April 24 (April) 
  • Pasqueflower (Anemone patens): April
  • Prairie-smoke (Geum triflorum): April 24 (April–May) 
  • Bloodroot (Sanguinaria canadensis): April 15 April–May
  • Wild ginger (Asarum canadense): April 24 (April–June)
  • Dutchman’s breeches (Dicentra cucullaria): April 24 (April–May)
  • Virginia bluebellsMertensia virginica): May 1 (April–May)
  • Woodland phlox (Phlox divaricata): May 1 (May–June)
  • Wild geranium (Geranium maculatum): May–June
  • Trillium (Trillium spp.): May 1 (May)
  • Shooting star (Dodecatheon meadia): May
  • Wild lupine (Lupinus perennis): May–June
  • Indigos (Baptisia spp.): May–July
  • Spiderwort (Tradescantia ohiensis): late May–June
  • Milkweed (Asclepias spp.): June–August
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