Garden Guide: September

September Gardening Guide for the Pacific Northwest

As September arrives in the Pacific Northwest, the maritime climate ushers in a noticeable transformation in our gardens. The shift in weather patterns, with cooler nighttime temperatures and increasingly overcast, rainy days, marks the beginning of the autumn season. This is a critical time for gardeners in Washington state to prepare for winter and ensure a fruitful spring. Here’s how you can make the most of your September garden, and how Eco-Restore can assist you in achieving a thriving, resilient garden year-round.

Winter Greens for a Continuous Harvest

September is the ideal time to sow greens that will be grown under a cloche for fall and winter harvest. Our maritime climate, while challenging, often surprises gardeners with the hardiness and productivity of these winter crops.

What to Sow Outdoors Under a Cloche:

Beet Family: Beets (for greens), Spinach, Swiss Chard: These cold-hardy greens will provide a steady supply of fresh leaves through the winter. Even with fluctuating temperatures, their resilience makes them reliable choices.

Carrot Family: (Chervil, Cilantro): Cilantro is a great choice for overwintering, as it can handle cold temperatures. By sowing now, you’ll have early greens in late winter when fresh herbs are a rare treat.

Mustard Family: (Arugula, Asian greens, Cabbage, Cress, Mustard*, Radishes, Turnips (for greens)*): These fast-growing crops thrive in cooler temperatures and will be ready for harvest by early winter. A traditional winter green, turnip greens are nutrient-dense and can withstand colder temperatures.

Sunflower Family: (Endive*, Escarole*, Lettuce*): Although these can be sensitive to extreme cold, they’re worth planting for their potential winter harvest. Even if some are damaged, others may surprise you by surviving and thriving.

* These are sometimes damaged by cold winters under a cloche, but sometimes not; try them anyway!

Overwintering Crops for Spring Harvests

These crops are meant to overwinter. Ideally, the seedlings should enter winter with just four to eight true leaves. This slow growth phase allows them to endure the cold, and as spring approaches, they’ll burst into growth, giving you an early harvest from late February through April—long before many gardeners even start planting.

Sow Outdoors in Late September for early spring harvest:

Carrot Family: (Caraway, Carrots, Chervil, Cilantro, Sweet Cicely): These herbs and vegetables are perfect for sowing now. Caraway and Sweet Cicely can add a unique flavor to your early spring dishes, while carrots will provide a sweet, early root harvest.

Grass Family: (Barley, Oats, Rye, Spelt): These grains serve as excellent cover crops, enriching the soil with organic matter and preventing erosion over the winter. Oats like Avena sativa are great for a nourishing infusion to drink daily.

Pea Family: (Snow Peas, Fava Beans): Fava beans are particularly valuable as they fix nitrogen in the soil, preparing it for spring planting. Snow peas can also provide an early harvest in the spring.

Valerian Family: (Corn Salad): Corn salad, or mache, is a tender green that’s hardy enough to survive the winter and provide fresh, mild-tasting leaves in the early spring.

Tips for Success:

Thinning: Thin your overwintering plants more than you would for a spring planting. Space them about twice as far apart to improve air circulation and reduce root competition for nutrients. This is especially important when using cloches, as it minimizes disease risk and ensures healthy growth.

Soil Preparation: Incorporate well-rotted compost into the garden bed. Fall’s mild soil temperatures allow soil bacteria to mineralize the nutrients in the compost, making them readily available to your winter vegetables. This will set the stage for strong plant establishment and growth. Cover crops and compost are key to supplying the necessary nutrients for plant establishment and success.

Hardy, Self-Sowing Annuals

Hardy, self-sowing annuals are invaluable for the organic gardener. These plants fill gaps in your garden and serve as reliable nectar sources for beneficial insects. Be mindful, though—they can become weedy if not managed.

What to Sow Outdoors in Early September:

These low-growing flowers are excellent for weed suppression and can be tucked in among perennials or shrubs.
Meadowfoam Family: Fried Eggs (Limnanthes douglasii)
Mustard Family: Alyssum (Lobularia maritima)

These taller annuals can stand alone or be mixed with large plants, adding vertical interest and beauty to your fall garden.
Buttercup Family: Larkspur (Delphinium ajacis) and Love-in-a-Mist (Nigella spp.)
Plantain Family: Moroccan Toadflax (Linaria maroccana)

Eco-Restore is here to help

At Eco-Restore, we understand the unique challenges of gardening in the Pacific Northwest. We can help you plan and implement strategies that align with permaculture principles, ensuring your garden is resilient and productive year-round. Whether you need assistance with soil preparation, selecting the right crops for overwintering, or integrating beneficial plants, our expert consultation services are tailored to meet your specific needs.

By choosing Eco-Restore, you’ll be investing in a garden that thrives not just in the growing season but throughout the year, maximizing your harvest and reducing the need for synthetic inputs. Let us help you transform your September garden into a sustainable, productive space that supports both you and the local ecosystem.

For more information or to schedule a consultation please contact us!