Quick Digs: Prepping and Overwintering in Salvia Gardens
In autumn, even while the days are bright and balmy, you may find yourself frozen with indecision about how to prepare your gardens for winter. Although frost, sleet, snow, ice storms and damaging wind all seem distant on a hot Indian summer afternoon, you know they are coming.
Perhaps you are wondering how to protect favorite sages (Salvia spp.) that you know won't survive local winter temperatures and freeze-thaw cycles without some help. Although we can't offer you foolproof solutions, we provide ideas to try in this first article of our Quick Digs series on winter mulching Salvias and overwintering them both outside and indoors.
Each Quick Digs series selects a central issue and offers a series of brief articles to help you deal with it. This time, we dig into ideas that can aid decision making about whether to leave things alone in the garden or shift into high gear for Operation Overwinter.
Some gardeners prefer taking their chances with tender perennials dying during winter; they leave plants in the ground or in pots outdoors. Others try a variety of methods, some of which can be time consuming, to help tender plants survive winter.
General Garden Preparation
Last year at this time, we blogged about fall cleanup in Salvia gardens and talked, in particular, on the issue of pruning. We warned against heavy trimming -- except for clipping spent flower spikes -- because hard pruning at this time of year exposes the hollow stems of sages, or any mint family (Lamiaceae) plants, to moisture that sinks downward and causes crown rot.
However, the benefits of trimming flower spikes outweigh risks, because their removal allows Salvias to focus on root growth instead of seed production. A strong root system helps perennials to leaf out in spring.
Aside from overwintering techniques, this Quick Digs series will discuss the benefits of benign neglect and letting Mother Nature determine the fate of any Salvias that you have been growing as annuals.
Choosing Whether to Rescue
Before pulling on garden gloves or grabbing rake, hoe and snippers for fall cleanup, it's helpful to decide whether you want to put effort into overwintering plants and have time to do it. For many gardeners, benign neglect is a valid choice.
Instead of worrying about root growth and removing flower spikes, you may prefer to let plants go to seed so they will provide winter food for songbirds. Not all non-native Salvias produce seeds, but birds, including Orioles, favor the ones that do.
In the spring, a leave-it-alone gardener observes the base of dead foliage for new growth and revels in plants that have survived. This experience may show you which parts of your yard are most protective for certain Salvias. It may also help you to select more cold-tolerant species for replacement of plants that have died.
Knowing the USDA Cold Hardiness Zone for your region aids decisions about whether and what to overwinter. If you have mostly grown Salvias that typically aren't perennial in your zone, then you can treat them as bedding plants. In spring, you can dig up any that didn't survive and add them to the compost pile.
But what if you want to save money on plants, can't bear to let a beloved plant die or just want to defy the elements?
If the answer is yes to any of these questions, then you need to identify plants requiring winter intervention and decide which ones you most want to rescue, what kinds of protection you can provide and how much time is available to achieve these tasks.
Deciding What and How to Rescue
Depending on the species in your garden, some plants may be hardy repeat performers that are well adapted to local climate and require little winter preparation, such as a bit of mulch.
However, more involved techniques are necessary for Salvias that typically are grown as bedding annuals in your region. The mission, if you choose to accept it, is to find some way to keep their roots alive.
There is no magic method that will work for every plant you want to overwinter; we can't guarantee any one technique. But we can offer ideas involving experimentation with old-fashioned techniques as well as more recent innovations.
Some plants may live and others may die. For some favorites, you may need to replant and try a different overwintering strategy a year from now. Frustrating? Sure. Yet it is a worthy quest that is bound to satisfy curiosity and please you when success occurs.
We share a number of ideas in the remainder of this series. Here are the posts in order from articles two through five:
- Putting Salvias to Bed with Winter Mulch
- Overwintering Salvias in Containers Outdoors
- Overwintering Salvias Indoors, and
- Treating Salvias as Bedding Plants.
Asking Questions Now
If you are done with fall planting, ready to begin winter preparation and itching to ask us some questions about overwintering, go ahead. Write or give us a call. We're always willing to be a sounding board and bounce around ideas with you.