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Back to News Learnings – October 16, 2020

Learnings

Plant Perennials before Winter

There’s still time to plant your perennials this fall. The cooler temperatures make autumn plantings easier on plants and gardeners. Follow these tips for an easy installation that will help your plant thrive come spring.

Planting perennials

A well grown plant can have a very dense root system, an advantage when planting. You don’t want to just plunk it in the ground, you’ll need to tease the root system open so there’s good contact between the roots and the soil you are placing it into.

To tease the roots open I use a root hook. – This is a traditional tool used in Bonsai to do just what you need to do here, open up the root mass. Start by gently pulling the hook down through the root mass, if it’s really tight you will have to apply a bit more pressure to open the mass. You will lose some of the roots but don’t worry, there will be plenty to sustain the plant.

Use a root hook to loosen roots

As you tease apart the outside mass, you’ll need to open up the center of the mass as well. You can gently tap the root mass against the heel of your hand or agitate it back and forth in your hand.  Once the root mass is opened and loose, it’s time to dig your planting hole.

You want the planting hole to be larger than the root mass, with the rule of thumb being to dig a hole twice the diameter of the root mass. Dig the planting hole with your tool of choice, a trowel, a gardening knife; I like to use an angled trowel.  Loosen and remove most of the soil from your planting hole. From the loosened soil in the hole, take some of it and create a dome in the bottom of the hole.  You want the crown (where the greens meet the roots) of your perennial to be at ground level or just a bit above.

Use an angled trowel to dig a hole for perennials

Once you have your perennial at the proper height, begin backfilling the hole with the remaining soil. Bring the soil up to the crown, maybe a little higher, then gently firm the soil around the root mass. Next, you will want to water it in. Gently wet the entire root mass. Now you want to mulch over the entire planting area. I prefer leaf mulch, but any mulch is fine. Don’t mulch too heavily around the crown of the plant, an inch or so in depth is fine, but you can mulch a little thicker as you move out from the crown. Give the planting one more good watering and it should be set to go into winter.

Add perennials to the garden in fall

 

Vic Piatt is the Gardens Manager at Mt. Cuba Center and a graduate of Longwood Gardens’ Professional Gardener Program. He has held many positions at Mt. Cuba, including Plant Evaluation Gardener and Rock Outcrop/ Scree Gardens Horticulturist.