UNITED STATES—Weather is variable everywhere. Climates and seasons are imprecisely regulating. They merely define predictable ranges of the elements of weather, such as temperature, wind, humidity, precipitation and cloudiness. As unusual as weather sometimes seems to be, it generally conforms. Winter weather is mild here, but sometimes leave vegetation frosted.
Frost was sneaky this winter, by occurring during nights between pleasantly warm days. All elements of the weather were within ranges that are normal for local climate, but their chronology was deceptive. Frost seemed unlikely after such springlike daytime weather. Some foliage was frosted only because protection from frost seemed to be unnecessary.
Frost is now unlikely for most local climates so late in the season. Only climates that are at significant elevation or significantly inland might still experience frost. Coastal and low elevation climates are generally past their last frost dates. Some climates experience no frost at all. Except for within the coolest situations, no more vegetation should be frosted.
There is no longer any need to delay the removal of frost damage.
Therefore, it is generally safe to prune and groom away unsightly frosted vegetation. It is no longer helpful to insulate undamaged vegetation below. Any new growth that pruning of this nature may stimulate or expose should be safe from frost. Within climates that lack frost, vegetation that gets shabby from chill might also appreciate pruning and grooming.
Pruning and grooming of frosted vegetation can be challenging. Many frosted plants are already actively growing in response to warmer weather. Their new growth mingles with their damaged growth that must be removed. Efficient separation of the two requires a bit of effort and persistence. Fresh and tender new growth is innately vulnerable to damage.
For example, small new shoots of angel’s trumpet break away very easily if bulky frosted stems fall onto or through them in the process of removal. New shoots of several types of canna emerge from the soil among old shoots while it is too early to cut the old shoots to the ground. Grooming is easier where it can happen earlier or for cannas that grow later.
Highlight: Candytuft
Alyssum is popular because of its lightly fragrant and lacy white bloom that lasts through most of the year. It seems to be more perennial than it actually is because it sows seed to replace aging plants. Candytuft, Iberis sempervirens, is a bit less prolific with bloom and fragrance, but otherwise resembles alyssum. Without seeding, it can be nicely perennial.
Candytuft does not get much larger than alyssum although it supposedly has potential to get almost a foot high and a foot and a half wide. Shearing after bloom phases enhances foliar density and subsequent bloom. Primary bloom occurs during late winter, spring, or perhaps early summer. Minor random bloom is possible at any time, particularly autumn.
Plants propagate readily by division of small tufts of rooted stems from within established plants. Alternatively, creeping outer stems develop roots if simply pressed into the soil or held down with stones. Pruning scraps are tiny and awkward to handle, but can grow as cuttings. When disturbed, candytuft exudes an aroma similar to that of related cabbages, which might be objectionable to some.
Horticulturist Tony Tomeo can be contacted at tonytomeo.com.