Winterizing perennials and vegetables
Gardeners herald perennials, not just for their beauty but also for their resilience. Known for their predictable winter slumber, each new year brings fresh green growth and a new vitality that promises to energize your garden, but you need to be sure to take steps in the fall to ensure they bounce back to their strongest. At the same time, while annual vegetables and herbs need to be replanted each year, some preparation before winter will benefit your vegetable garden in the spring. All it takes is a little care when it comes time to tuck your garden in for the winter.
Know your zone
The first step in winterizing your garden is to figure out your zone. The US Department of Agriculture provides a Plant Hardiness Zone Map (http://www.usna.usda.gov/Hardzone/ushzmap.html), which divides the country into zones based on winter temperatures. Then, you'll want to check when the first average frost and freeze dates are for your area. Winterizing perennials requires a few simple steps that are rooted in the same basic preparation principles, regardless of your location, but when to get started depends on your area’s traditional frost date. Just before the average frost date is a good time to begin. Pay attention to your plants—when their leaves start to brown out and cooler days have become an ordinary occurrence, it’s time to get out your tools.
Clean-up 101
This is a perfect time to clean up your flower garden. Pull out stray weeds (you’ll thank yourself next spring) and dead annuals. You can put the dead annuals in your compost pile, along with other organic matter, like fresh grass clippings, spent vegetable and flower plants and kitchen scraps, but avoid putting the weeds in, especially if they've already gone to seed. You don't want to be replanting weed seeds when you amend your soil come spring. Their seeds can overwinter in areas of the pile that don’t break down completely.
Now that you’ve gotten out the annuals and the weeds, it’s time to take stock of the perennials that are left. Before cutting any plants back, horticulturists recommend cleaning your clippers by spraying them with a fungicide and checking to be sure they’re sharp—it’s important to get a clean cut, as jagged edges can introduce disease. When your clippers are ready, it’s fine to cut your perennials back to a few inches. Compost the twigs and extra organic matter.
Don’t forget your vegetables
The same basic perennial clean-up tips apply to your vegetables, which by now have surely seen their better days. Dig out dry bean vines and slouchy tomato plants. Pull determined weeds and bolted spinach. Feed it all to your compost pile, except the weeds. After your vegetable garden is all cleaned out, take time to improve your soil, tilling in fresh manure. Now is a great time to apply uncomposted manure because any disease organisms will break down and die before next spring. (Remember never to spread fresh manure on your garden while plants are present—your plants could get contaminated.)
A caveat to compositing garden waste: While you should remove all diseased plants—including vegetables with late blight—from your yard, take care not to compost these plants. They should either be thrown out or burned so that the disease is away from your property.
Why all the fuss over garden clean-up? Weeds left in the garden will seed themselves. Bugs love nothing more than spending their winter vacation in a big pile of leftover plants, weeds and vegetable matter; the last thing vegetable gardeners want is to fatten them up for the spring. And insect pests that feed on rotten plants in the late summer lay their eggs on the old plants, where they hatch in the spring.
Bed-time vitamins
Before the onslaught of frost, consider adding a high-potassium fertilizer to your perennials. The numbers on fertilizer bags can be confusing, but for this task, the third number is the one to remember: It represents the percentage of potassium represented in the mix. Potassium benefits plants in a few ways, but one of the most known is its ability to guard the plant against diseases and aid in drought protection and cold tolerance. Not only that, but potassium improves root development—perfect for the start of winter. It helps repair the cells within the plant as it eases them off to sleep.
The merits of mulching
In the winter, soil often freezes, and when it thaws, plants’ roots are at risk. Mulching with shredded leaves, pine bark, pine needles or straw gives your perennials an extra layer of insulation, which protects shallow root systems that are more susceptible to the cold. You’ll find that mulch also helps to control weeds. Apply loose, airy mulch about 2-4 inches deep. Mounding mulch much deeper than 4 inches may attract mice and voles. If there are trees around your perennials, don’t pile the mulch too high around tree trunks, which could cause decay.
And what about your herbs? Annuals, such as basil, cilantro and dill should be either repotted to spend the winter indoors or composted. Perennial herbs like rosemary, lavender, chives, mint and sage are known as “tender perennials” and can make it through the winter in most climates but should have plenty of mulch, preferably shredded bark, to get them through the harsh weather. Like perennial flowers, they should be cut back, but by no more than 1/3 of their height.
A garden put to bed
After your garden is tucked in for the winter, take time to make a few notes in your gardening journal. Did the new tomato variety you tried yield as many plants as you had hoped? What week did you plant your basil, and would you plant it earlier next year? Next spring, when you and your garden are well rested, you’ll be glad you kept a record.
Don’t forget you can also share your gardening notes in the comments area below. Or, let us know a few of your own tips for winterizing perennials and vegetable gardens.