Garden center plants in trays.

Fall Garden Planning: A Great Time To Plant

Fall Garden Planting

The summer-to-fall garden transition proceeds in September, while garden tasks continue: planting, weeding, and collecting or ordering seeds. This month is also a good time to take stock of the garden, reflect on the season, and look ahead to changes.

When a wildflower gardener tries to emulate this process, we do all we can to "help nature along." That means, we clear the area, open the ground, provide good seed-to-soil contact for every seed, water if necessary, and do anything else to assure our seeding's success. It's easy and the work is the same as required for a spring planting. In fact, some people think fall planting is easier.

There are two big advantages to planting in the fall in that you have more time to plant and weed control is much easier. Read the 5 tips on fall planting.

1. When to Plant

Tree nursery in fall

The ideal period for fall planting is roughly six weeks before the first hard frost. In northern areas of the country the ideal planting period might even be late summer. In general, the window of opportunity for most folks is during September and October.

Why is fall planting so good? In the fall, the warm soil encourages root growth. Roots continue to grow through the winter until the ground freezes – in areas with mild winters roots may continue to grow. In early spring roots begin new growth or continue to develop at a faster rate and begin top growth. While the same plant planted in spring gets a slow start due to cool soils, the fall-planted plants are becoming well established.

2. What To Plant

Spring Blooming Ephemerals: Spring-blooming perennials, especially in the bare root form, are best planted early in the fall. Planting in the fall while the soil is still warm will give the roots enough time establish properly. This allows the plants to emerge from well-established roots, with a stronger start, the following spring.

Trees and Shrubs: Native trees and shrubs can be planted this in September, providing weeks of warm soil temperatures for the plant roots to establish before soil temperatures drop. You will not see much growth above ground, but new roots developing now will provide a quick start for your plants next spring.

Ordering Plants and Seeds: Native plants and seeds can be ordered and shipped now for fall planting. Take care; regional nurseries may include species that are not native to your area.

For information on native plant nurseries see: Wisconsin Native Plant Nurseries

Planting Seeds: Delay planting seeds until after frost. This will keep grass seeds from germinating before good growing conditions return in spring. Also, many forb seeds require a cold treatment to break dormancy; our Wisconsin winter can provide this. In addition to sowing seed in prepared areas, you might plant some in flats and over-winter them outdoors in your garden.

Transplantation: In September, plants can be divided or transplanted from existing native gardens. Use the current habitat (where the plant is thriving) as a guide to choosing new locations.

See the Wisconsin native plant guides listed at the end of this article for a selection of plants for every need!

3. Soil Temperature

Fall garden in brilliant color

The soil temperature is warmer in the fall than it is in spring, and this encourages root growth. And since the plants are usually not producing flowers, they’ll have more energy for root establishment.

4. What About Frost?

Frost will stop the growth of the plant above ground, but it will not kill the plant. The roots will continue to grow until the soil freezes solid.

For more information on protecting plants from frost and freezing see: Protect Your Garden From Winter

5. Plant Condition and Dormancy

At the end of the growing season many of our native perennials have finished their growth cycles, and they may not be looking their best. Spring ephemerals are completely dormant in the fall, with no growth showing above the roots. Because of this complete die-back, ephemerals are often shipped as bare root stock. Plants that bloomed earlier in the summer will also be well past their prime and may look very tired as they head towards winter dormancy. Simply plant them with the same care that you would bestow upon a thriving green plant in the spring.

At the end of the growing season many of our native perennials have finished their growth cycles, and they may not be looking their best. Spring ephemerals are completely dormant in the fall, with no growth showing above the roots. Because of this complete die-back, ephemerals are often shipped as bare root stock. Plants that bloomed earlier in the summer will also be well past their prime and may look very tired as they head towards winter dormancy. Simply plant them with the same care that you would bestow upon a thriving green plant in the spring.

Plant Guides:

 Wisconsin Native Flowering Shrubs
 Gardening With Wisconsin Native Grasses
 Wisconsin Native Fruit Trees
 Wisconsin Native Berry Shrubs
 Pollinator-Friendly Ground Covers

Bees flying footer graphic