Recording spring bloom data gets underway around the first of April and is a daily occurrence starting around mid-April. It was apparent around this time that many of our earliest flower displays had been greatly compromised due to uncharacteristic and wildly fluctuating weather patterns over the 22’/23’ winter season. While the winter began on a very mild note, February saw extreme and persisting cold temperatures. Spring-blooming flower buds (that develop on previous year’s growth) suffered freeze damage from these cold temperatures which dipped as low as double digit negatives, leading many flowering tree and shrub species to exceed their critical temperature. Critical temperature is the temperature at which cold injury is likely to occur to flower buds, which differs depending on species as well as the growth stage of the bud. As the bud develops, it is less and less tolerant of freezing temperatures. Having experienced mild weather in January, the cold hardiness of these spring flowering buds was reduced and therefore more susceptible to damage.
For example, Forsythia buds begin to die around -5°F. Our forsythia had a very weak showing in the spring, only blooming where they had been protected by layers of ice or snow. Species most consistently damaged by the extreme temperatures in February, however, were our spring blooming azaleas, rhododendrons, and flowering fruit trees. Our cherry trees suffered damage to not only their flower buds, but their leaf buds as well, leaving some to leaf out later in the season, and some to die all together.
A second damaging freeze happened in mid-May (on the 18), with temps holding in the low 30s for much of that morning damaging later season fruit crops such as apples, grapes, and strawberries. As we don’t grow for fruit production on Great Hill, we do not have documented data on these losses ourselves but learned of the losses from neighboring farms and local cooperative extensions. Below, we’ve outlined trees, shrubs and vines effected by these events on Great Hill.
RHODIES
Rhododendron ‘Vinecrest’- None
Rhododendron ‘Anah Krusche’- None
Rhododendron ‘Boule De Neige’- None
Rhododendron ‘Boursault’- None
Rhododendron ‘Westons Pink Diamond’- None
Rhododendron ‘Summer Rose’ – Few
Rhododendron ‘Goldflimmer’- None
Rhododendron ‘Lavender Queen’- None
Rhododendron ‘Pauline Bralit’- None
Rhododendron ‘Red Quest’- None
PJM ‘Purple Gem’- Few
‘Compacta’- Few
‘Victor’- Few
Rhododendron ‘Janet Blair’- None
Rhododendron ‘Karen’- None
Rhododendron ‘Renee Michelle’- None
Rhododendron catawbiense ‘Album’- Few
Rhododendron ‘Westons Pink Diamond’- None
Rhododendron ‘April Dawn’- Few
Rhododendron maximum ‘Summer Snow’- Few
‘Independence’- Few
Rhododendron ‘Cunninghams White’- None
Rhododendron laetevirens ‘Wilsonii’- None
Rhododendron yaku- Few
Azalea ‘Komo Kulshan’- Few
Azalea ‘Hebert’- Few
Azalea ‘Amoena’- None
Azalea yedoense var. poukhanense- Few
Azalea ‘Delaware Valley White’- None
Azalea ‘Springtime’- None
Other Shrubs/Vines
Pieris japonica- None
‘Compacta’- None
‘Browers Beauty’- None
‘Dorothy Wyckoff’- None
Forsythia x intermedia ‘Gold Tide’- Few
Roses- Shrub- Underwhelming year
Hydrangea anomala petiolaris- Few
‘Tuff Stuff’- Few
Wisteria macrostachys ‘Blue Moon’- None
‘Aunt Dee’- None
floribunda ‘Macrobotrys’- None
TREES
Styrax japonica ‘Pink Chimes’- None (leaf bud death as well)
Pyrus calleryana ‘Aristocrat’- None
Prunus autumnalis- None
Prunus subhirtella- None and leaf bud death
‘Rosy Cloud’- None and leaf bud death
‘Pedula’- None and leaf bud death
‘Snow Fountains’- None
Still Performed- Magnolias, Dogwoods, Crabapples, Enkianthus, Fringe Tree, Kalmias, Viburnum, Koelreutaria, Lilac, Hibiscus, Fothergilla, Weigela, Spiraea, Cotinus, Stewartia, Crataegus