Guide to Root Division for Herbs

Guide to Root Division for Herbs

By Juliet Blankespoor, Herbalist, Teacher, Gardener, Writer and Botanical Photographer

Following is adapted, with permission, from the Chestnut School of Herbal Medicine’s 1,000-hour Herbal Immersion Program. The program is the most comprehensive handcrafted online herbal course available. Learn more at Chestnut School of Herbal Medicine..

root division two plantsAs a gardener, you’ve undoubtedly bought many plants to populate your garden, but you can’t beat the satisfaction of propagating your own. Dividing roots is perhaps the easiest and least expensive way to quickly fill your garden with mature plants. In a nutshell, this involves digging up a plant and separating a portion of the root system, and then replanting the separated portions, or divisions. The daughter plants, or divisions, may be planted directly in the garden or potted in preparation for moving to a new location. Depending on the plant, it’s possible to make more than 20 divisions from just one mother plant.

When you propagate a plant by root division, the new plant will be an exact clone of the parent. This is how we maintain a specific set of desired traits, such as height, flower color, flavor, aroma, or any number of distinct qualities that allow for that plant to stand out from the rest of its species.

Most herbs can be divided through root division, especially plants that run or clump. I don’t recommend dividing plants with taproots or a single stem, as they typically won’t “take.”

root division toolsEarly fall and early spring are the best times to divide roots because plants are more dormant. In the fall, just make sure to divide your roots before too many hard freezes, as the cold can stress your divisions. You’ll want to divide roots when the ground isn’t too wet, as the soil will be clumpy and adhere to the root system, making it challenging to get to the roots and see what’s going on.

To start, its best to gather a digging fork, pruners, flat-ended shovel, and a Japanese digging knife, or hori-hori. The digging fork is especially helpful, as the tines minimally disturb the soil. The blade of a Japanese digging knife has a sharp or serrated side to saw through difficult roots. Finally, some roots are just so tough that you’ll need to jump on a flat-ended shovel to sever them.

 Step-by-Step Guide to Root Division

  1. Dig the plant. Choose a vigorous, large plant that can withstand some stress. Use a digging fork or shovel to loosen soil in a circle around the plant. Gently pry plant from soil, excavating side roots if needed.

 

  1. Remove excess soil. Shake away just enough soil to see what you’re working with. You may need to thump the root system in its hole to dislodge soil clumps. Be careful, as removing all the soil will damage the tender microscopic root hairs.

 

  1. Size up the root system. Determine how many buds or shoots the root system has and decide how many cuts to make, yielding a few large divisions or many small divisions. Each plant is truly unique in how small of a division will actually survive. Be certain to have at least one shoot or bud per division and a large enough root system to support it.

Root division hori hori

  1. Make divisions. Using one of the tools mentioned above, divide your roots. For roots that are growing loosely, pry apart divisions with your hands. Denser root systems may require sawing into segments with a hori-hori. And tough root systems require a shovel.

 

  1. Trim the tops. This is the most important step in successful root division. When you disturb the root system, the plant can no longer support the original aboveground vegetation. If the plant is dormant, you can skip this step. If your plant is an herbaceous perennial that is already dying back for the winter, you can completely cut back the aboveground growth. If the plant is actively growing with many stems, cut the stems back by half. If it just has emerging leaves, remove half the leaves. If you’re replanting the mother plant, make sure to cut back its growth as well.

Root division cutting back

  1. Transplant into the garden or pots. Transplant “divisionlings” into their forever home in the garden or pot them. Make sure to plant at the same soil depth they were originally growing. Potted divisions can be grown until their root system is established and has filled up the pot, and then they can be transplanted or shared with a friend.

 

  1. Water. Water your divisions with fresh water or prepare a solution from willow or seaweed that encourages rooting.

 

  1. Enjoy.

HSA (2)The Chestnut School of Herbal Medicine is located in the botanically rich Appalachian Mountains, outside of Asheville, NC. Their passion for healing plants, herbal education, and medicinal gardening is at the heart of all their teachings. Their online courses: the Herbal Medicine Making Course, the Herbal Immersion Program, and the Foraging Course (launching in early 2018).

 Juliet Blankespoor is the botanical mastermind behind the Chestnut School of Herbal Medicine, which she founded in 2007 after deciding to become a professional plant-human matchmaker. She has more than 25 years of herbal experience.

Prepare Garden Soil for Growing

Prepare Garden Soil for Growing

By Kelly Orzel, author, master gardener and owner Bowery Beach Farms

soilTest.-¬KellyOrzelPhotographyWhen most gardeners think about their garden, they picture big beautiful blooms or perfectly ripe tomatoes…I think about what’s underneath: Dirt. (Sidenote: I would bottle that scent and wear it if I could!)

But first things first, test your soil. The importance of soil testing cannot be overstated. Most vegetables prefer a pH of 6.5, but without a starting point you won’t know whether you need lime to raise it, or sulfur to reduce it. Your results also tell you which amendments to add if you want to grow brassicas, nightshades or something else. Soil test kits are available at your local extension office and for a nominal fee you’ll get all sorts of helpful information (it’s worth the investment).

Don’t scrimp on soil. I saw it time and again when I worked in the nursery, weekend warriors trying to save a few bucks on inferior soil, while spending huge amounts of money on dahlia tubers, new seeds or bright, colorful annuals and perennials. This ADES (All Dirt Is Equal Syndrome), affects many new (and experienced) gardeners, and can be disastrous in the garden!

soil.compostAmended.-¬KellyOrzelPhotographyLet’s dispel soil myth #1 first:  Topsoil is not the answer. “Topsoil” means the dirt was scraped from the top, including troublesome weed seed. It doesn’t indicate if it has organic matter (which you want) or what percent of sand, silt and clay is in the bag. What you really want instead is loam. Loam has just the right balance of soil particles, giving you excellent drainage and improved nutrient and water-holding capacity (yes!). Look at soil bag descriptions and look for something that drains well.

Every year I start with a soil test to determine what my plants are going to need and add accordingly (blood meal for foliage, bonemeal for flowering plants and lime/sulfur to adjust the pH). Just follow the directions on the bag and apply.

A note on digging. Unless you are starting a brand-spanking new bed, DON’T DO IT ! This is soil myth #2: Rototilling mixes your soil. No. It doesn’t. Actually, it breaks apart your soil’s structure and kills the beneficial microbes and worms living in your garden.

soil.Feat.-¬KellyOrzelPhotographyInstead, top dress your beds with a few inches of compost and let the earthworms do the work. It’s what they want to do anyway and they’re good at it. They’ll sense that delicious, nutrient-rich compost ladled on top of your garden bed and crawl up, around and down as fast as they can to digest nutrients, leaving castings and distributing nutrients throughout the soil. Why would you want to mess with the natural order of the universe?

For new raised beds, fill them with a 50/50 mixture of garden loam and compost, topping it with a few inches of straight compost. Otherwise, all the same principles for amending and no tilling apply.

Soil myth #3: You need to aerate your soil. Wrong-o. While you want some space in your soil for air, water and roots to tunnel through and reach nutrients, let the soil microbes handle that. This is why good soil structure is so important (remember that mix of sand, silt and clay we talked about?). You don’t want too much sand because that will cause all your water and nutrients to drain away before plants can get a hold of them, and you don’t want too much clay either, which causes root rot. With the right blend of soil particles, earthworms and microbes not only till, but they aerate as well, leaving behind hundreds and thousands of channels as they slide, inch and wiggle their way through your garden.

Osoil.Bed.-¬KellyOrzelPhotographynce your bed has been made (ha!) and planted in, try to avoid stepping on and compacting the soil. Each time you compress the soil, you’re squeezing out all those air channels and suffocating the roots.

As you plant into your beds and notice an increase in earthworms, that means you are doing something right! Earthworms are a sign of healthy, biological activity in your soil. If you don’t see as many worms as you like, you can add casting to help improve the fertility, buy actual earthworms and toss them into the garden or raise your own in a homemade earthworm bin (there’s lots of free plans available online).
Personally, I use drip tape and landscape fabric (rated for 12-15 years) with holes burned into them, and plant directly into these little pockets to help control the weed situation.

BackyardGardenerBook.KellyOrzel.-¬KellyOrzelPhotography 2While most of us hate weeds because they make the garden look sloppy, but they’re extremely dangerous because they steal all that organic matter and water from your plants, and overcrowd your garden. To make it look more aesthetically pleasing you can cover the fabric with wood chips, straw or gravel.



For more information on soil, its amendments and nutrients, compost, as well as everything you can (and can’t) imagine about organic growing and the kitchen garden, pick up a copy of Kelly’s book, The Backyard Gardener, available on Amazon
Barnes+Noble’s or get your signed copy on her site, Bowery Beach Farm.


Kelly.Orzel.BoweryBeachFarmKelly Orzel is an author, girl-farmer, garden speaker, Master Gardener and life-long grower of green things. With more than 20 years of experience and a master’s degree in Horticulture, Kelly’s obsession for plants and flowers has culminated with Bowery Beach Farm in Maine. As a sustainable, organic farmer she specializes in culinary herbs and scented geraniums.  

Aside from dirt, Kelly loves bread and cheese, over-sized sweaters and Jane Austen novels. For more information on Kelly and her garden lectures, contact her here! You can visit her and her farm at BoweryBeachFarm.com.