How to Revive a Succulent With Frost Damage
Did your favorite succulent get left out in the cold for too long? Take heart, and read on as gardening expert Melissa Strauss explains how to mitigate the damage and get your succulent on the fast track to a full recovery.
Frost damage is something most cool climate gardeners deal with at some point. Those early cold fronts roll in surprisingly fast some years and leave your warm-weather plants looking pretty sad. Since many succulent plants are not frost-tolerant, it’s not uncommon for them to be counted among the wounded when an unexpected frost creeps up.
If your succulent was accidentally left out in the cold, it could look pretty sad afterward. Don’t despair just yet, though, because frost damage doesn’t always equal a death sentence for succulents. You can take steps to help your succulents recover from frost damage and protect your plants in the future.
Step One: Move Your Plant
Whether the frost crept up on your garden or you just hadn’t gotten around to bringing in your succulents for the winter, the best thing to do when you suspect frost damage is to mitigate any further damage by moving your plant indoors as soon as possible. While some damage may already be done, salvaging the plant could hinge on preventing any further stress.
Many succulents begin to show stress as the weather cools before a frost even takes place. A fair number of these plants will show that they are experiencing cold stress by changing color, usually taking on a red or purple tint. This shift can be desirable and attractive, but if you accidentally leave your plant outdoors for too long, you might get more than you bargained for.
Whatever the case, it’s best to bring your succulent indoors to alleviate further stress and allow it to focus energy on recovering from frost damage. Try to avoid placing your plant in direct sun, as most of these plants prefer filtered or indirect light. Place your succulent in a spot with plenty of indirect or diffused light.
Step Two: Identify the Frost Damage on Your Succulent
Not all succulents are intolerant of frost, so before you start cutting away at your plant, ensure that the damage is caused by cold and not some other factor like overwatering. Sempervivum and Sedum are both frost-tolerant types of succulents that can tolerate quite a great deal of cold weather. If you have one of these plants that you suspect is suffering, it is probably some other factor causing the damage.
For frost-sensitive succulents, the amount of cold exposure plays a role in how extensive the damage is, and the full extent of the damage may not be immediately visible. A light frost (29-32°F/-1-0°C) may only damage the ends or surfaces of leaves, while a longer freeze (below 28°F/-2°C for more than two hours) can damage all or nearly all of the exposed foliage.
A hard freeze will typically kill the roots of most succulents. If the temperature dropped into the 20s (~-6°C) while your plant was outdoors, you may want to prepare for the worst. It can take a few days to weeks for the full extent of the damage to reveal itself, so try to be patient about moving forward or removing foliage.
Step Three: Wait and Observe
Once your plant has been indoors for a time, you should begin to see the effects of the frost damage on your succulent. Succulents store water in their plump, fleshy leaves. When exposed to freezing weather, the moisture in the leaves crystalizes and damages the cells.
This cellular damage shows up gradually in the form of wilting and discoloration. Leaves may turn brown or black at the edges first. The damage is extensive if these characteristics affect all of the foliage and the stems begin to collapse. This is why waiting is an important step.
You want to leave as much healthy tissue as possible to promote maximum photosynthesis. Any healthy foliage should be preserved. It should become clearer within a week or two which parts of the plant are damaged.
It is best to wait until the plant begins to recover before pruning. Allow the frost-damaged portions to dry out, and watch for signs of new growth. This may take place at the tops of stems if the damage was only to the plant’s leaves. If the stems are damaged, new growth will appear at the base.
Step Four: Prune Away Dead Foliage
Once new growth has appeared, you can clearly determine the extent of the damage. Then, it’s time to remove the dead portions. Use a pair of clean, sharp scissors to gently trim away portions of foliage and stems that are dead.
Sterilize your scissors or other tools with alcohol to avoid contaminating the plant with fungus or bacteria. Your plant will be vulnerable for a while, and open wounds are an added vulnerability. Once the cuts heal over, your plant will be much stronger, and it can begin directing more energy to new growth.
Sometimes, the process of freezing and thawing will push the plant’s roots up above the soil level, leaving them exposed and vulnerable. If this has happened, cover the roots gently with a bit of succulent potting soil to insulate and protect them.
Step Five: Propagate Just in Case
This step is optional, but if you are concerned that your plant may not recover, it’s a good idea to propagate so that you don’t lose the plant altogether. Most succulents can be propagated successfully with leaf cuttings.
Gently remove a couple of healthy-looking leaves from the plant and allow them to cure for a few days. This means leaving them in a dry, dimly lit area. You want the ends of the leaves to form a callous before putting them in the soil. Don’t let the cutting fully dry out. Once the cut end of the leaf has healed over, you’re ready to propagate.
Fill a container with moist potting mix. Then, simply set your leaf cuttings on top of the soil. Place the container in a warm spot with plenty of bright, indirect, or diffused light. Keep them out of direct sunlight, as this will cause more stress.
Your cuttings need moisture to grow, but you don’t want to rot them by keeping them soggy. Instead, use a spray bottle to mist them whenever the soil looks dry. Over the next few weeks, you should see small leaves and roots begin to form at the cut ends of the leaves.
Succulents are slow growers, so hold off for a while before transplanting your new baby plants. When the cutting dries up and falls off, your plantlets are ready to move into their own containers.
Step Six: Minimize Stress and Take Care
Over the next few months, the objective for your parent plant is to minimize stress as much as possible. You currently have a plant that has endured a lot of stress, and it needs a bit of TLC to recover. For succulents, that means leaving them alone as much as possible. Strive to maintain a consistent environment.
Once you have pruned off the damaged tissue, allow the cuts to heal before watering your succulent. Once those callouses have formed, give your plant a good soaking, and then water it once every two weeks going forward. Succulent roots are sensitive to overwatering, so ensure that your container drains well after watering.
Continue to keep the plant in indirect sun to prevent further stress from sunburn. While a bit of sun stress can be very pretty and isn’t likely to cause harm, a succulent trying to recover from frost damage needs as little stress as possible.
Keep the plant in a warm spot in the house, as succulents prefer warm weather. Keep an eye on your plant for changes, but in general, handle it as little as possible and try to keep conditions stable and static.
How to Prevent Succulent Frost Damage
Moving forward, there are several ways to protect your succulents against future frost damage. Some of the steps you can take to keep your succulents thriving in cold weather are:
- Keep the soil moist – Water your succulents before a possible frost to protect the roots, as the moist soil prevents freezing pockets of air around them.
- Cover your plants – Cover your succulents with a light blanket or frost cloth overnight when you suspect freezing weather. This protects the foliage and roots. Just remember to take the blanket off in the morning to allow the plant to breathe and get the sunlight it needs.
- Avoid pruning late in the season – Pruning your plants encourages new growth, which is more vulnerable to cold than mature growth. It also stresses the plant slightly, so you don’t want a plant that is trying to heal to be exposed to other stressors. Do your pruning in the spring instead, when the plant is actively growing and heals fastest.
- Bring your succulents indoors – If possible, bring your frost-tender plants indoors for the winter. If this isn’t possible, relocate them to a space that is under cover and keep their containers close together for added protection.
Frost damage can be a worrisome issue to contend with, but it doesn’t always mean certain death for your succulents. Succulents are surprisingly resilient and recover fully from this kind of stress. But they do need some extra care and minimization of any additional stressors in the meantime. A little patience and some TLC should have your succulents on the road to recovery in no time.