previous
  • 10 Seed-Starting Tips
    10 Seed-Starting Tips
  • Seed Starting in Speedling Trays
    Seed Starting in Speedling Trays
  • Pick Plants for Fragrance
    Pick Plants for Fragrance
  • Garden Design Basics
    Garden Design Basics
  • Go Green on the Patio
    Go Green on the Patio
  • NEW Video Series: There's a Better Way
    NEW Video Series: There's a Better Way
  • Homegrown / Homemade
    Homegrown / Homemade
  • Pantone Color of the Year 2014: Radiant Orchid
    Pantone Color of the Year 2014: Radiant Orchid
  • 3 Ways to Design with Containers
    3 Ways to Design with Containers
  • Rex Begonias
    Rex Begonias
  • DIY A-Frame Veggie Trellis
    DIY A-Frame Veggie Trellis
  • Building Better Borders
    Building Better Borders
  • How to Grow Mustard
    How to Grow Mustard
  • Using Containers as Elements of a Design
    Using Containers as Elements of a Design
  • Plant Finder: Spring Plants
    Plant Finder: Spring Plants
  • Bold and Beautiful Zinnias
    Bold and Beautiful Zinnias
  • Indoor Seed Starting Materials List
    Indoor Seed Starting Materials List
  • 10 Combinations for Shade
    10 Combinations for Shade
  • Planting the Right Way
    Planting the Right Way
  • Black Plants Done Right
    Black Plants Done Right
  • Get your FREE Everyday Roses download now!
    Get your FREE Everyday Roses download now!
  • 20 Gardenworthy Self-Sowers
    20 Gardenworthy Self-Sowers
next

continued 1| 2| 3next>View all

Grow more plants with root cuttings

Use this simple technique at the right time to multiply some of your favorites

The major benefit of root cuttings is the simplicity of the process. Four easy steps can produce a large number of plants without requiring fancy equipment. This method of propagation requires that most of our efforts take place in very late autumn or very early spring, two times when we have a short list of gardening chores. The ensuing growing season will find your new plants filling out, and by the fall, they should be ready for a permanent place in your garden design.

Uncover the roots when the plant is dormant

Root cuttings are most effective if taken when plants are dormant, usually between November and February. This timing maximizes the stored energy in the roots and minimizes the stress on the parent plant. Once a plant breaks bud in the spring, energy begins to move out of the roots and into the plant, reducing the effectiveness of root cuttings. I also make sure the parent plant is well hydrated and was not under drought stress when it went dormant before I take any cuttings.

When collecting roots on smaller plants, such as perennials, I find it easier to simply lift them in their entirety. For shrubs, I unearth some of the roots on one side of the plant, digging in close proximity to the base to ensure I find roots belonging to the right plant. I then trace them out from the plant until I have a suffi­cient length to take several cuttings.

Make sure you find the right root. Digging close to the base of your shrub ensures that you get roots from the right plant. Make sure you find the right root. Digging close to the base of your shrub ensures that you get roots from the right plant.
Then make sure you choose a living root, not a dead, black one. Then make sure you choose a living root, not a dead, black one.

Choose roots that are pencil thick

Shrub roots can get quite large and woody, but the best ones for cuttings are those approximately as thick as a pencil. These are young, vigorous roots that are more likely to send up new shoots. With perennial roots, thicker is better. I use a sharp pair of pruners to make a straight cut at the end of the root closest to the parent plant. At the far end, I make a diagonal cut. This helps me maintain the root’s original orientation, critical to the production of new roots and shoots. I always avoid cutting off more than one-third of the roots because this may eliminate too much of the plant’s stored energy.

I then take the long pieces of root I removed and cut them into sections 3 to 6 inches long, making sure to cut the ends closest to the plant straight and the ends farthest from the plant at an angle. The optimal length is 3 to 6 inches because it ensures that there is enough energy in the cutting and, in some cases, enough dormant buds to produce roots and shoots.

After taking the cuttings, I replant the mother plant or cover the exposed roots. Then I water the area thoroughly to remove large air pockets in the soil and settle the roots back into their home.

Place the cuttings in soil, and wait

To get the most out of my cuttings, I treat perennials and woody plants differently at this stage.
Place perennial roots horizontally because they can send up shoots from several places along a cutting. Place perennial roots horizontally because they can send up shoots from several places along a cutting.

Perennials
I like to propagate perennial root cuttings in flats because they produce shoots quickly and have the ability to break bud in several places along the root. I place the cuttings horizontally, ½ inch deep, in a flat of moist potting soil (photo, above). To maintain high humidity, I cover the flat with a plastic bag or a pane of glass and place it under lights.

Woody Plants
If I’m working with cuttings from a woody plant (photos, below), I tie them in a loose bundle with like ends together. To locate the cuttings after storage, I wrap them with bright marking tape, allowing a few extra feet to hang from the bundle. I dig a hole below the frost level and place a few inches of sand in the bottom to ensure that the cuttings don’t rot from poor drainage. I then place the bundles with the slanted ends facing down in the bottom of the hole and refill it.

Tying the cuttings in a bundle makes them easier to find when it is time to dig them up. Click to enlarge image Tying the cuttings in a bundle makes them easier to find when it is time to dig them up.
The entire hole doesn’t need to be filled with sand. But it is essential in the bottom to reduce the potential for rot. Click to enlarge image The entire hole doesn’t need to be filled with sand. But it is essential in the bottom to reduce the potential for rot.
Colored tape or some other type of marker wrapped around the cuttings and sticking aboveground will keep you from planting on top of the bundle. Click to enlarge image Colored tape or some other type of marker wrapped around the cuttings and sticking aboveground will keep you from planting on top of the bundle.

Plant new shoots outside, and keep them moist

Cuttings stored in the ground should be ready to lift within three to four weeks but can stay buried for much longer if the weather remains too cold for them to be planted outside. When they are unearthed, the cuttings will likely have roots and, occasionally, some small shoots forming on the cuttings. Even if I see neither sign of growth, I still move forward, unwrapping the bundle and separating the cuttings. I plant the cuttings in freshly prepared, loose garden soil, setting them vertically, 12 to 18 inches apart, with the tops of the cuttings (the straight ends) approximately 2 inches below the soil surface. I mark the area well to prevent planting something else in the same place. As the temperatures rise, I make sure the cuttings stay moist. In a few months, new shoots should be apparent, and they will welcome a light solution of water-soluble fertilizer.

Perennial cuttings grown inside can sprout quicker than their outdoor counterparts. After several shoots emerge, I remove the protective covers, feed them with a half-strength solution of liquid fertilizer, and, if the plants are sun lovers, supply ample light. Just like seedlings, these new shoots will need to be gradually introduced to the rigors of outdoor life before they can be planted in a permanent home.

A new shoot A new shoot
Time for shoots to become plants. To help the transition, provide some TLC in the form of moist, fertile, loose soil. Time for shoots to become plants. To help the transition, provide some TLC in the form of moist, fertile, loose soil.

The best plants to start from root cuttings

 Woody Plants

Figs
(Ficus carica) zones 6–9
Glory bowers (Clerodendrum spp. and cvs.) zones 7–11
Hydrangeas (Hydrangea paniculata and cvs.) zones 4–8
Lilacs (Syringa vulgaris cvs.) zones 4–8
Mock oranges (Philadelphus coronarius and cvs.) zones 4–9
Oregon grapehollies (Mahonia aquifolium and cvs.) zones 6–9
Pussy willow (Salix discolor) zones 4–8
Raspberry (Rubus biflorus) zones 6–9
Red- and yellow-twig dogwoods (Cornus stolonifera and cvs.) zones 3–8
Rose of Sharons (Hibiscus syriacus cvs.) zones 5–9
Roses, nongrafted types (Rosa spp. and cvs.) zones 2–11
Sumac (Rhus typhina) zones 3–8
Trumpet vine (Campsis radicans) zones 5–9
Weeping willow (Salix babylonica) zones 6–9

Perennials

Barrenworts (Epimedium spp. and cvs.) zones 4–9
Bear’s breeches (Acanthus mollis) zones 7–11
Blue stars (Amsonia spp. and cvs.)  zones 3–10
Cardoon (Cynara cardunculus) zones 7–10
Colewort (Crambe cordifolia) zones 6–9
Comfreys (Symphytum spp. and cvs.) zones 3–9
Garden phloxes (Phlox paniculata cvs.) zones 4–8
Hollyhocks (Alcea rosea cvs.) zones 3–9
Japanese anemones (Anemone X hybrida cvs.) zones 4–8
Japanese aster (Kalimeris pinnatifida) zones 5–9
Joe Pye weed (Eupatorium fistulosum) zones 3–8
Oriental poppies (Papaver orientale and cvs.) zones 3–9
Pasque flowers (Pulsatilla spp. and cvs.) zones 4–9
Sea hollies (Eryngium planum and cvs.)  zones 5–9

Rose
Cardoon
Hollyhock
Garden phlox
Trumpet vine
Pasque flower
Oriental poppy
Weeping willow
From Fine Gardening 111 , pp. 41-45

continued 1| 2| 3next>View all