It can be frustrating when plant cuttings fail to root and instead start rotting. However, there are several common reasons why cuttings rot, and adjusting your methods can often resolve the issue.
Common Causes of Rotting Cuttings
Here are some of the most common causes of rotting plant cuttings:
- Using non-sterile tools – If the scissors, knife, or shears used to take cuttings are dirty, bacteria and fungi can be transferred to the cutting.
- Poor sanitation – If the surface used to prepare cuttings is dirty, pathogens can infect the stem.
- Overly wet soil – Wet soil lacks air pockets needed for healthy root growth and promotes rot.
- Dense soil – Compacted, dense soil prevents oxygen from reaching newly forming roots.
- Excess humidity – High humidity encourages fungal and bacterial growth that leads to rot.
- Insufficient light – Low light levels inhibit evaporation, keeping cuttings too wet.
- Improper temperature – Temperatures that are too high or fluctuate widely encourage rot.
- Poor stem condition – Cuttings from weak, stressed, or diseased stems are more prone to rotting.
- Incorrect planting depth – Planting the stem too deep can lead to rotting.
- Using the wrong rooting hormone – Excessive or inappropriate hormones can damage and rot cuttings.
Tips to Prevent Rotten Cuttings
Here are some tips to help prevent rotting of plant cuttings:
- Use clean, sterile cutting tools to reduce disease transmission.
- Prepare cuttings in a clean environment using sanitized surfaces.
- Avoid overwatering cuttings and ensure the rooting medium drains well.
- Use a loose, lightweight rooting mix that contains perlite or vermiculite.
- Keep humidity around cuttings moderate, not excessive.
- Give cuttings bright, filtered light, not full sun or dense shade.
- Maintain consistent temperatures between 70-75°F for most cuttings.
- Take cuttings from healthy, vigorously growing plants.
- Make sure at least 2 leaf nodes are buried in the rooting medium.
- Use the correct type of rooting hormone and proper concentration.
Treating Rotten Cuttings
If you notice cuttings starting to rot, here are some treatment options:
- Improve airflow and reduce humidity – Increase air circulation and allow cuttings to dry out more between waterings.
- Apply fungicide – Use a fungicide drench to kill fungi causing rot and prevent spreading.
- Trim rotting parts – If rot is localized, trim off all diseased, mushy stems and re-plant.
- Treat with cinnamon – Dusting stems with cinnamon has anti-fungal properties that can stop rot.
- Propagate in water – Transition rot-prone cuttings to root in water instead of wet soil.
- Re-cut the stems – Take new, sterile cuttings from non-infected parts of the plant.
How to Improve Success with Plant Cuttings
Here are some key tips for dramatically improving your success with rooting plant cuttings:
- Take cuttings first thing in the morning for maximum hydration and vigor.
- Use sharp, sterile pruners or scissors to get clean cuts that heal rapidly.
- Make angled cuts rather than straight across to expose more surface area.
- Keep cuttings cool and moistened until sticking them into rooting medium.
- Remove all flowers, flower buds, and all but the top 2 leaves.
- Dip the base of cuttings in the correct rooting hormone for that species.
- Stick cuttings in pre-moistened, well-draining soilless mix up to the first leaf nodes.
- Use bottom heat of 70-75°F to encourage better root growth.
- Cover cuttings to create a greenhouse environment while rooting.
- Keep soil moist but not saturated while roots form.
Conclusion
Rotting cuttings can be very discouraging, but is often due to just a few key issues with overwatering, high humidity, unsterile tools, or improper temperatures. With some simple adjustments to your propagation methods, you can greatly improve success rates and enjoy an abundance of rooted cuttings. Be sure to start with healthy parent plants, use very sharp tools, prevent disease transmission, and control moisture carefully. With a little practice, you’ll be rooting cuttings like a pro!