September ushers in shorter days and milder temperatures. No need to mention frost just yet — but keep it on the back burner. Focus on dividing perennials for an even more spectacular garden next year, and harvesting whatap in season.
Choosing which plants to divide
For gardeners, success has a broad list of outcomes — blooms from spring to fall, delicious fruit and vegetables or a healthy lawn. All are good, but nothing shouts victory like dividing plants to get more free plants.
Overgrown or crowded perennials need attention. Now is the time to move them for a head start on next year’s garden. They’ll have the rest of the fall to get their roots established so next spring, they’ll perform even better.
First, do an inventory. Remove plants that just aren’t working or thriving in the garden.
Dividing is necessary when foliage or flowering look sparse, or the center of the clump is dying out or hollow.
If you’re unsure what plants need division, the general rule is to divide spring and summer bloomers in the fall and fall bloomers in the spring. For ornamental grasses, spring division is recommended.
Dividing or not is based on how the roots grow underground — they don’t all grow the same way.
The easiest plants to divide grow with fibrous root systems, such as clumpers like daylilies and hostas. Also easy are beebalm and goldenrod roots, which spread and use their shallow stems (rhizomes) to cover the ground. Thick-rooted plants with woody crowns like peony and baptisia are more challenging and require digging several buds and healthy roots.
Plants that have a long tap root or woody shrub-like structure, such as butterfly weed, lupine, clematis, false indigo, lavender and baby’s breath, should be left alone.
For a helpful resource on dividing the various root systems, visit
.
How to divide plants
Water the plants a couple of days before dividing and cut the foliage down to 6 to 8 inches for ease of move.
First, dig the new hole location and amend the area with a little compost and mostly existing soil. Native plants and succulents will benefit with added small aggregate like expanded shale for better drainage.
Move mulch away from the plant to be divided. With a straight edged shovel, dig straight down in a circle around the entire plant.
Next, with the shovel, either lift up the entire root ball to divide while it is exposed as a large clump, or dig down into the plant and take out sections including roots or rhizomes.
Re-plant at the same height in the ground as the previous location. Fill in soil around the root ball and water well. Additional soil may be needed after watering. Then mulch.
Fill out the garden
Shop garden centers for late-season plant deals. Some plants may look root-bound or struggling, but the root systems should be in good shape, so give them a try. Score or cut all four sides of the root ball with a knife or scissors before planting so the roots reach out, grow and get established.
Let some plants form seed heads to save for planting this fall or next spring. Hybridized plants will likely not come true to flower since they have different parents. When the flower heads dry, collect the seeds by shaking them into a paper bag. Move dry seeds to a clean, dry jar or plastic bag, label and plant seeds next year. Learn more at .
Plant seeds of quick maturing cool-season veggies now. Get them growing while temperatures are warm. Later, when temperatures get colder, use easy, often free or low-cost materials to create cold frames so plants can continue to grow through the fall.
Radish, kohlrabi, short-rooted carrots, lettuce, spinach, arugula, kale and other leafy greens can be direct seeded. Look for varieties that mature in less than 50 days. Tuck in seeds anywhere there is a bit of room or in containers.
Pinch new flower clusters on tops of tomato plants so energy will go toward ripening existing fruits.
For a list of fruit, vegetable and herb harvest and storage tips, refer to this helpful chart at .
