winter-veggies

Get started growing cool season crops

Gardeners in the Pacific Northwest are lucky enough to be able to grow vegetables all winter long. Early planning and planting are essential.

This article will go over some basic guidelines, but the most important is to remember that gardening should be fun. With a little bit of planning ahead you can have a great winter garden and be eating home-grown veggies all year long!

Keep in mind that each winter is different, so is each winter’s harvest.

Saving space in your garden when you are planting in spring is one way to ensure space is available when it is time to plant your fall and winter crops. Sometimes you can harvest one crop and then use that space for something else, but many fall crops will need to be planted during the time when your summer garden is in full abundance. When you start thinking about your garden as a year-round space it may change what you choose to plant and when.

For example, many gardeners wait and plant their broccoli and Brussels sprouts in fall rather than spring because the starches turn to sugar after a hard frost so the veggies taste better.

Here at Portland Nursery, we carry vegetable varieties that we expect to perform well in the Portland area. There are also catalogues and seed companies that offer a wide selection of other varieties for our climate.

Our job is to help you be successful, so if you have any questions please ask!

Timing

The biggest challenge to winter gardeners is timing. Many seeds must be planted when our summer gardens are at their fullest, and our minds are furthest from winter.

The average first and last frost dates in Portland are October 15 and April 15. Between these dates plants grow slowly. Vegetables you grow in this period will need to be established enough to survive the cold and shorter day length.

There are three main ways to extend your season of harvesting:

  1. Plant a second crop of squash, beans, lettuce, etc. in June for a fall harvest.
  2. Plant fall crops so that they ripen by November 1 to harvest through March.
  3. Get overwintering varieties in so that you get a head-start in spring!

Start planting seeds in July for your fall & winter harvest.

Often there isn’t space in the garden to plant your seeds in July. You can either set aside space when first planning the garden and seed directly, or you can start seeds indoors to be planted after summer crops are gone. Starting seeds indoors also makes it easier to keep the seedbed moist for germination, which can be difficult outside in July.

If you choose not to direct seed, using starts that you bought or grew allows you to transplant outside four to six weeks later.

Site Preparation & Location

In the northwest, abundant rain can drown winter crops. Make sure your planting area is well-amended and drains thoroughly – no crops succeed in waterlogged soil. Consider “mulching” around your crops with a cover crop that will help absorb the abundant moisture, but wait until October to plant it, or else it may outgrow your crops.

Carefully consider where to plant your winter garden based on sun, protection from wind, and convenient access. You are unlikely to make a long, dark, muddy hike out to your plants, and your summer vegetable patch may not receive any of the low rays of winter sun.

Surprisingly, winter veggies can also suffer from too little water. Plants need to be well-hydrated before cold weather, since our cold snaps are usually dry. In the event of a forecasted cold front, make sure the ground is moist, and water if it is not.

Protection

Many gardeners enhance their winter growing capabilities with plant protection. Cold frames, cloches and frost blankets all provide some protection; greenhouses provide a lot. For best results, plan on using one of these methods. You may enjoy the increased growth rates that come with these tools, or you may prefer seeing what succeeds without any protection at all.

winter kale
winter squash

Pests

Happily, cold weather kills most pests. Aphids can sometimes be a problem, but there are many treatment options. Keep in mind that many summer-time solutions are unavailable in winter. Ladybugs and other beneficial insects are dormant and many chemicals require a certain air temperature to be effective.

Storage

Many summer crops can be stored for winter consumption, most notably winter squash and potatoes. Root vegetables can be grown in winter or summer, and stored in the ground or in another cool location.


Crops & Varieties

Many crops do well in cooler weather, or even prefer it. Spinach, lettuce, kale, broccoli, carrots and garlic are among the most common vegetables that succeed in Portland-area winters. Arugula, collards, leeks, mizuna, and radishes are among the less-common vegetables that thrive in cooler weather.

The crops that do not succeed in winter are the traditional summer garden crops: beans, corn, cucumbers, eggplant, peppers, squash, and tomatoes. Anyone trying to grow those in cold weather would quickly conclude that “winter gardening” is impossible.

Within crops, there are varieties that prefer heat and those that like it cool. Read seed packets and catalogs, choosing cold-season varieties. “Fall Blend” mixes are usually a good choice, offering diversity and an extended harvest.

Overwintering varieties are crops that you plant in fall and then harvest in early spring. If the weather stays warm enough before the first frost, often you can harvest a little bit before the plant goes dormant for the winter.


Macro - Micro Climates

The information in this brochure is for the Portland metropolitan area, at levels below 500 feet. Growing in areas that are above 500 feet or exposed to cold winds requires additional protection. Even within cities, neighborhoods, and yards, subtle climate differences exist based upon how trees and buildings block wind and sun.

Additional Resources

For estimates of planting times on a wide variety of crops please see our: Veggie Calendar: Guidelines, Tips, and Timing for Planting Vegetables.

More excellent resources: