Post #64B Making New Plants by Layering and Grafting
Post Description: How to make new plants by layering and grafting.
Welcome to the second post on making new plants, fun stuff! Propagating is a wonderful skill to add to your gardening repertoire.
In the last post we discussed growing plants from seeds and cuttings, which is a common way to plant annual edibles and some perennial varieties.
Today we are discussing layering and grafting which is a more common method for propagating trees and shrubs. This is where science meets a little bit of magic in the process of growing new plants from existing plants. There are several ways to layer and graft, we’ll discuss the most common (and simple) ways here.
Layering
Layering is a method of propagation where shoots of a plant are encouraged to grow roots of their own while still attached to the parent plant. Once a shoot produces roots, it is removed from the parent plant and planted on its own.
There are several ways to layer for propagation:
Simple Layering – this method works well with trees and shrubs 1-2 years old whose new growth can bend to reach the ground.
- Gently wound the stem by making a shallow, diagonal cut where you intend to bury it.
- Bend the stem to the ground and secure in place with a ground or garden staple.
- Cover the stem portion in soil. It can take anywhere from 3-12 months before the new growth is ready to be separated from the parent plant.
Tip Layering – this method works especially well for raspberries and blackberries.
- Follow the method for simple layering, but instead of putting soil on top of the surface, dig a narrow 4 inch hole and insert the tip of the branch or vine into it.
- Back-fill the soil and secure it with a garden staple if needed.
Compound Layering
- Follow the method for simple layering but repeat the process several times along one branch or vine to propagate multiple new plants.
Mound Layering
- Bury shoots or new growth at the bottom of a plant. This will encourage the new upward growth, or shoots, to also root downward.
- Once the shoots have produced healthy roots, separate them from the parent plant.
- A variation is stooling, where you hard prune first, then bury new growth once it has reached 6-8 inches.
French Layering – a combination of stooling and simple layering.
- After a hard pruning, allow new growth to flourish for a year.
- Then trim off the tip of the branch or vine and follow the simple layering method with the flexible new growth.
Air Layering – a method for branches that are not bendable or will not touch the ground.
- Douse some sphagnum moss in a bucket of water and drain.
- Strip the leaves and outer bark of the section of branch you are using down to the woody part.
- Wrap the damp moss around it, then wrap with plastic wrap.
- Cover with aluminum foil to block out light and conduct heat.
- Check on it after 3 weeks. If the roots have wrapped around the moss it is ready to separate from the parent plant.
Layering Tips
- Wound the plant to induce root production – gently wounding plants will promote auxin, a growth hormone found naturally in plants that encourages root growth, to concentrate around that spot.
- Light deprivation – restrict light to encourage root, rather than shoot, growth. This can be done by mounding dirt or wrapping a section of branch in aluminum foil.
- Choose your plants wisely – healthy, established plants with plenty of new growth and easily bendable branches or vines are best for this technique.
- Try a rooting hormone – Auxin can be purchased as a powder at your local nursery. Apply as directed to give your plants some extra rooting support.
Grafting
This technique is used largely for fruit trees and some ornamentals that can be difficult or impossible to grow from seeds or cuttings.
Grafting combines a healthy rootstock (think well-rooted and established trunk) with a scion, or fruiting branch.
Grafting benefits include repairing trees damaged by weather, reproducing a particular fruit from a prized tree, increasing productivity, and the creation of hybrids which may be less prone to disease and stronger overall.
There are several grafting techniques, depending on factors such as what your end goal is, how old the rootstock and scion are, and where you plan to graft on the tree.
Grafting Tips
- Scions (branches of desired varieties) of more northern plants should be cut when they are dormant in the Fall. Tropical scions are best collected when the parent trees are just beginning to put on new leaves, but before the branch tips start growing longer. Label your scions and keep them cool and moist with their cut ends in a damp layer of sphagnum or sawdust.
- Graft tropical trees as soon as you can after collecting scions, more northern ones in Spring. For all, wait until the buds on your rootstock are just beginning to open. This will ensure the tree is pushing most of its nutrients towards the tips of the branches to encourage new growth. Find out when this is likely to be for the type of plant you are grafting. Tropicals may go through this cycle several times a year.
- Use the right tools – Make sure your tools are sharp. Clean and disinfect between grafts if you are doing more than one to ensure no transmission of pests or disease between trees.
- Position the scion with precision – be sure the inner bark of the scion and rootstock are connected to ensure proper fusion and growth. This is the green area just underneath the brown outer bark. Make sure the scion is right-side-up.
- Protect and bond – use bonding sealant and tape to secure the graft and keep out pests and disease.
- There are several types of graft – read up on these and choose the types to experiment with. Try propagating a lot of rootstock plants from cuttings several months before and cut extra scions so you have a bunch of material to work with.
Have you experimented with layering and/or grafting? Have you had success or are you on a steep learning curve? It won’t always take, especially with grafting, so keep on trying.
Propagating requires patience – we know from experience around here!
Share your thoughts and ideas with the rest of us, or ask a question – we’ll likely have an answer or know where to find one.
Until next time,
Happy Gardening!
Mary