Gardening with Jennifer: Transplanting

This is the second gardening article from Jennifer Rotermund, who will be a regular contributor to the ShorelineAreaNews.

by Jennifer Rotermund with input from Emily-Robin Pierce

Photos by Jennifer Rotermund

As with life, a garden is always a work in progress. Sometimes, even our best laid plans can benefit from a change or a little updating. Our gardens are often an extension of ourselves, an expression of our current interests or style - both of which have a habit of changing and evolving throughout our lifetime. Perhaps you’ve changed your mind about a design or a “theme” of a particular part of the garden (I once had the grandiose idea of creating a native alpine meadow garden in my front yard then realized my property’s full sun exposure, and the fact that I live at about the 500 foot elevation level rather than 7,000, lent itself a little better to growing vegetables instead - who knew!). Maybe a tree was taken down on or next to your property and what was once a shade garden is suddenly and literally seeing the light of day. Or sometimes, you just wake up one morning, look out a window into the backyard and decide that the Rhododendron you planted on one side of the yard would be a better fit on the other side - oh, hind-sight, if only we could inject you directly into our eyes, we’d never need glasses again.

Luckily for us, these amazing life forms we call plants are quite forgiving of our whims and will tolerate the trauma of a transplant - as long as we follow a few basic rules. (Note: these rules apply especially to small trees, shrubs and perennials that the average person can move on their own. For large trees and shrubs, call in the help of a professional to help and advise you in person) 

1. Transplant ONLY in the Spring or Fall - its a traumatic experience for a plant to be moved from a spot where its been growing comfortably for a while to a new spot, even if that new spot has been lovingly prepared or may even be a better spot for that plant in the long run. Even a plant coming directly out of a restrictive nursery pot experiences some stress when its pulled from that environment and placed in your garden. A lot of water and cool, cloudy weather conditions go a long way to ease that stress. Transplanting during our Northwest Spring and Fall seasons (with their moderate temperatures and frequent precipitation) will give you the best chance at success. If you’d like to test that theory, try transplanting on a hot day in the summer...I’ve lost many plants that way!

2. Disturbing the root system is good for the plant and is often necessary - ok, I know it is scary to deal with the root system of a plant; we’re talking about its critically important life-center here. But if you’re going to move a plant, you’re going to disturb its root system. If done correctly, your plant will thank you for the disruption. As an added myth-busting bonus, cutting a root stimulates it to grow! For established perennials, shrubs and small trees, cutting the roots at between 6 inches and 2 feet out from the trunk or main stalk of the plant will ensure you have a root ball you can move with ease. Use a sharp pair of hand-pruners that you’ve clean and sterilized with alcohol (our hand pruners often carry and transmit a lot of plant diseases). For plants coming out of a container, break-up and loosen the root ball until the roots are pointing roughly out and away from the plant - it is not natural for roots to be formed into the shape of the container in which they’ve been sitting. Prune away any roots that have permanently taken the shape of the container and are growing in a circular pattern around the root ball. If allowed to continue growing, these roots will eventually “girdle” the root ball, restricting its overall ability to function and will prematurely kill the plant.

3. Dig a planting hole that is only as deep as the height of the root ball, but roughly twice as wide - believe it or not, most plant roots grow horizontally, not vertically. So now that you’ve gone through the trouble of freeing the plant from its previous location, give its roots a healthy jumpstart in its new home. When placing the plant in the new planting hole, make sure that its horizontally directed roots can lie down flat, straight and fully extended. If you have to curve or bend the roots to get them to fit in the hole, that hole is not wide enough.

4. Install a woody-stemmed plant with its root flare even with the surrounding surface soil level - the root flare is the part of the trunk or main stem of a woody-stemmed plant that literally flares out into the top of the root ball. That root flare must be at the soil surface level (not below) for the plant to thrive in the future. Only the root ball itself should be below ground and touching the soil. (For some pictures of root flares and how they look when they’re planted properly as opposed to being buried, run a Google image search of “root flare”)

5. Soil amendments are usually not needed - unless you have pure sand or pure clay, or live on top of a large rock, your soil is probably just fine for growing most plants. Especially when moving a plant from one location in your yard to another, that plant will be happiest in the type of soil - your soil - to which its already grown accustomed. Additionally, water will only flow freely through uniform soil mediums. In other words, any soil amendments you choose to add, need to be mixed thoroughly with your existing soil until the two are combined uniformly. Any soil “layers” created by throwing soil amendment into the planting hole on top of existing soil can redirect water flow in the future away from your plant’s roots. Any potting soil around the roots of a potted plant from the nursery should be removed and discarded. Potting soil around the roots of a plant you’ve placed in the ground can become hydro-phobic and and repel water completely. Your plant needs to adjust to the soil in its new location; placing it directly into that soil alone will help it adjust more efficiently.

These tips should give you a good foundation for success with transplanting or installing plants in your yard, but as with everything, there is a lot more information available. Likewise, transplanting or installing a plant might inspire you tackle other new projects in your garden. For further information or to expand on the information I covered in this article, I recommend the book, The Informed Gardener by local author, professor and horticulturalist Linda Chalker-Scott. It is easy to read and understand, is a treasure-trove of practical gardening information, and is written with our Northwest region in mind.

Jennifer Rotermund is the Lead Gardener for Garden of Weedin’ (a local pesticide-free garden maintenance company), owner of Gaiaceous Gardens (an edible landscaping business with a teaching garden/urban farm and certified wildlife habitat located in Shoreline) and a Habitat Steward.

Emily-Robin Pierce is a local horticulturalist and a gardener with Garden of Weedin’

Also by Jennifer: Xeriscaping