You’ve probably heard of “zone denial” – planting things that are marginally winter hardy in an area and hoping they make it through, by mulching, planting against a south facing wall, praying, and so on. Some years they do, some they don’t. (“It grows in Mexico, maybe it’ll make it here, oh please oh please oh please.”) For the rest of us, we can plant flowers that are cold-temperature tolerant to start with, and, for that, nothing beats pansies.
Pansies flower and look their best in cool weather; that is, in fall and in spring. They may be either fall- or spring-planted. They will usually be in bloom when you purchase them, and, if fall-planted, continue flowering into December or later. They stop blooming during the cold of winter, when temperatures are consistently below freezing, but if given some care, the plants will hunker down and survive the cold.
As the days get warmer in March, pansies begin to flower again, and look downright spectacular in April and into May. As the temperatures get hot going into summer, the plants get leggy (stretched) and the flowers get smaller. In our climate, they generally look so miserable in summer heat that gardeners replace them with summer annuals.
As recent immigrants from Germany in 1930, the Behnkes were used to fall-planting pansies, and promoted the idea here, where the practice was uncommon. Even early on, pansies were an important item for Behnke Nurseries, with tens of thousands of seedlings planted out in the ground or beds for sale in strawberry cartons in the fall.
The primary winter-care requirement is to make sure that the soil is watered if it gets dry. Pansies are shallow-rooted, so a couple of weeks without rain or snow signals the need for water. Same thing for your evergreen shrubs, especially broadleaf evergreens like camellias or rhododendrons. This has to be done when the ground isn’t frozen to do any good, preferably after several warm, sunny days that occur occasionally in winter. A light mulching in late fall will hold moisture in the soil and reduce frost heave. Frost heave occurs when the ground freezes and thaws, and the freezing squeezes rocks and recently planted plants out of the ground.
The other thing you can do for your pansies is reduce desiccation from the wind. “Desiccation” is drying out: you know that winter air has low humidity, causing your skin to dry out. Plants continue to lose moisture to the air, even if the ground is frozen, especially when planted in an exposed location and it’s windy. If they lose too much they reach what is called the “permanent wilting point.” This means they won’t revive even if watered; they’re dead; they’re pushing up daisies.
Snow is the best protection from wind, but if snow is lacking, to reduce the drying power of the wind, you can make a mini-windbreak. Another European and Behnke tradition is to use leftover Christmas greens. Branches cut from a discarded Christmas tree and laid upon the pansy bed give protection from the wind while letting some light into the plants. If you don’t celebrate Christmas or you have an artificial tree, consider stopping at a Christmas tree lot after Christmas for a post-holiday special. At that point the tree will be cheap or free, as you are saving the lot owner the cost of disposing of the tree.
So: for loads of color in fall, and a repeat performance in spring, plant pansies, keep them watered through the winter, and if necessary, protect them from drying winter winds. And if you want to grow mangoes outdoors, move to Hawaii.
by Larry Hurley