June 1, 2013
Colorado Springs got the April showers, but where, many gardeners and lawn owners are wondering, are the May flowers?
Dead, fooled into blooming by the early arrival of spring weather and killed or damaged by the nearly two weeks of freezing weather that followed.
"You had that (early bloom) and you get the quick frost and those delicate little blossoms that come out ... They bloomed very early and the frost nipped them," said Richard Sexton, master gardener at the Colorado State University Cooperative Extension.
Plants have a type of anti-freeze that keeps them alive while dormant in winter, but they become vulnerable as warm weather arrives, buds form and leaves sprout. According to Denver-based Swingle Lawn, Tree & Landscape Care, even hardy native trees such as pines, spruce and junipers suffered the loss of foliage and twigs. Ice crystals form in plant cells, which become dehydrated and die.
And the tulips that came up in April never had a chance.
"The severe damage caused by our sudden, unprecedented and sustained freeze is only now becoming apparent," said Swingle CEO Tom Tolkacz.
According to the National Weather Service, temperatures in the 60s and 70s were common in late March and early April. But on April 9, the mercury dropped to 10 degrees. It hit 8 degrees April 10 and 13 degrees April 11. Below-freezing temperatures occurred again daily April 15-25.
Sexton said the ongoing drought made trees and plants more vulnerable.
"In a normal year, if the trees and plants are healthy, they can shrug off the occasional frost or plant or bug disease. When they are already stressed from the drought, they are simply more vulnerable to all those things."
Withered flowers, brown, crumbly buds, dead needles and dry, brittle twigs are common signs of damage. Swingle experts recommend removing damaged sections of trees and using foliar spray fertilization for damaged ornamental plants.
Trees and plants can't repair damage, so encouraging new growth is the only option. Dead annuals won't regrow until next spring. Fruit tree owners will have to wait until next summer if the buds died.
"About the only thing they can do is watering and fertilizing. The rest of it is sort of up to God," said Sexton. He recommends consulting a professional arborist if a valuable tree is damaged.
New leaves may emerge and some trees and plants may produce secondary buds for flowers. Even with ample watering, expect to see some distortion of the tree and an early yellowing and dropping of leaves in late summer.
But while the trees may look a bit unhealthy, take heart: Tree roots are resistant to freezing temperatures, and for a tree's survival, that's a lot more important than having green leaves or colorful flowers.
"Eighty percent of what's going to happen to that tree, good, bad or indifferent, is in the ground. That's where the root system is. That's where it gets its food, water and nutrients," Sexton said. "As long as that's viable, the plant's probably going to grow and survive."
For many of the older transplanted trees in medians and rights-of-way in Colorado Springs, the dry, cold winter could be the death knell. While they aren't flowering trees and didn't lose buds to the freeze, city forester Paul Smith said he has seen "a ton of damage and die-off." The weather limited irrigation, and with residential watering restrictions in effect this summer, many are stressed to the breaking point.
"We're going to lose a bunch of the older trees in downtown medians this year," Smith said. "Colorado Springs was a treeless plain when it got here and that's what it wants to be again."