With the exception of garlic, September is the last month to plant annual edible crops In the Pacific Northwest. Plants need a minimum of 10 hours of daylight to grow and by the end of October the daylight hours have grown too short for crops to mature. October 31st may be just around the corner, but the good news is that even though growing season will eventually end, your harvests can continue well into the winter!

How to prepare your garden for a winter harvest:

1. Make room for fall crops by removing crops that are mature and will not hold up against a frost. It may still be a little early to pull out crops such as tomatoes and peppers, but potatoes and onions are often done producing by late summer and can be pulled to make room for fall crops. These crops also have a long storage life outside of the garden, often keeping for up to six months after they are harvested! For a quick guide to storing root crops, click here.

2. Plant one last round of short season, frost sensitive crops. There are more than 8 weeks between now and the last 10 hour day, and almost 10 weeks between now and the estimated first frost date so that leaves plenty of time to plant crops such as lettuce and radish. These crops will start to decompose in the garden after the first frost, so be sure you have also planted plenty of frost tolerant crops that will hold up in the cold weather.

Frost sensitive, short season crops that can be planted now are:

Bok choi (T)
Head lettuce (T)
Lettuce (D)
Radish (D)

4. Plant frost tolerant crops for a winter and early spring harvest. Frost tolerant crops are crops that will hold up against the cold weather. Though they don’t mind the cold, like other crops, these plants still need at least 10 hours of daylight to grow. A good goal is to plant your crops early enough so that they are at least 75% mature by the time the days become shorter than 10 hours, also know as the Persephone. If well established by the end of the growing season, these crops can not only provide a winter harvest but will likely start growing again early in the spring before the freshly planted spring crops have a chance to mature. For example, healthy, well-established fall broccoli will provide a harvest before the end of the growing season, but if left in the garden it may also sprout tons of new florets in the spring (see photo).

Frost tolerant crops that can be planted in late summer are: