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The Wisconsin Garden in September

The summer to fall transition continues in September. The days can be summer-like at the beginning of the month, and downright chilly, possibly even frosty, by the end. The typical garden tasks of planting, weeding, and watering continue, it is a good time to take stock of the garden, reflect on the season, and look ahead to changes.

When to Plant:

Because of the changing temperatures at this time of year, timing is important. The ideal time for fall planting is about six weeks before the first frost. This could be as early as mid-August in Wisconsin. In general, mid-August to mid-September is ideal. Plant warm season perennials and grasses while the soil is still warm. Cool season perennials and grasses can be planted later as the soil cools.

What to plant:

Spring Blooming Perennials: especially bare root, are best planted in early fall. Planting in the fall, while the soil is still warm gives the roots enough time to establish. The plants then emerge in spring with a strong start.

Dig, divide and transplant spring and summer blooming perennials that have outgrown their location, failed to flower, flop open, or died out in the center. Also, it’s not too late to dig, divide and move Iris that are crowded or bloom poorly. And finally, peonies that should be moved or shared, can be dug and divided at this time and until mid-October.

Trees and Shrubs: Trees and shrubs, planted in September, provide weeks of warm soil temps for the plants to establish. You won’t see much, if any growth, above ground, but new roots are developing until the ground freezes.

Order Plants and Seeds: like spring bulbs now, will give you the best selection. But don’t plant them yet. Wait until after a hard freeze, but before the ground is frozen.

Keep watering as needed: Make new plantings, evergreens, and moisture-loving plants a priority.

Of course, there is lots of other things to do depending on what kind of garden you have. And lots of information about what to do at this time of year in whatever garden you have. The internet can be a great source in this regard.