Will Frost Hurt Your Succulents?

Succulents from certain parts of the world, notably lower elevations of South Africa and Madagascar, are vulnerable to freezing temperatures. If the forecast is for temperatures below 32 degrees F, throw a sheet over your crassulas, kalanchoes, aeoniums, stem euphorbias and aloes before nightfall and remove it in the morning. See how I do it in my own garden in this video, Protecting Your Succulents from Frost.

Frost that nips your succulents may turn their leaves brown and unsightly. How do you know if a plant is worth keeping? It may depend on how patient you are. Even badly damaged succulents are surprisingly resilient, but it may take months before they look good again.

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Temperatures below 32 degrees caused the fluid in this aloe’s cells to expand and burst, irreparably damaging the tips of many of its leaves. Luckily for the plant, those same leaves protected its core, which is still green and viable.

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If you decide to try and salvage a succulent with this sort of damage, wait until the weather warms in spring, then snip off the dead tissue. Because new growth forms from the center of the rosettes, pretty soon the old leaves will be barely noticeable.

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And now you know that this is one succulent that needs covering next time there’s a frost advisory for your area. Here’s how my garden looks when temps are predicted to drop below 32 degrees F.

Notice that Agave attenuata tucked beneath the tree on the left? It’ll be fine because the tree will protect it. The plants you have to worry about are those that are out in the open, with nothing above them. I sometimes stand over a succulent and gaze upward. If there are no tree limbs or eaves directly overhead, it gets draped. (I use old sheets. Several years ago a nongardening friend, stopping by for a visit, asked if I was doing my laundry.)

How do you know if you live in a frost-free area? Your neighbors grow Agave attenuata in their gardens, and the plants look fine. In my garden, this soft-leaved agave is the canary in the mineshaft where cold is concerned.

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It’s the first plant to show damage from frost in winter. A lot of succulents can handle cold below 32 degrees for short periods. But Agave attenuata will look like this the next day. This is a nuisance, but fortunately not fatal.

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See the healthy green part of each leaf? Wait until spring, then use scissors to trim off the tissue-paper-like frozen tips, cutting each leaf to a point. When you’re done, the damage will be barely noticeable. By summer new growth will have hidden the short lower leaves.

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What about a succulent that has frost damage only on its leaf tips? Don’t bother to trim them. It’ll lose those oldest leaves in a few months, anyway.

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Kalanchoes tend to be quite frost-tender. One similar to this melted to the ground in my garden at 27 degrees, and I assumed it was a goner. Fortunately I didn’t dig up the damaged plant and discard it, because a few months later…

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…it came back from the roots.

Jade plant is another widely cultivated succulent damaged at 32 degrees. The leaves turn squishy and putty-colored. This is not pretty, but if the plant’s stems are firm, it will recover and grow new leaves.

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Actually, the jade plant in the photo was not a victim of frost. You know the term “frost burn?” This plant actually was burned…by a wildfire. The only indication that it wasn’t “burned” by frost is that frost tends to damage the top of a plant. This one was scorched on the side closest to the fire. (Which just goes to show, succulents cook rather than burn, but that’s a different post.)

If you live in an area where you can’t grow most succulents in the ground because it gets too cold, take heart…there are varieties that will do well for you. I recommend this excellent book: Hardy Succulents by Gwen Kelaidis, photos by Saxon Holt.Screen shot 2016-01-05 at 7.59.00 PM

6 replies
  1. Linda Fleigner
    Linda Fleigner says:

    Another timely post. My cacti and succulents are all safely put away but sometimes time to laziness gets in the way and I may not get to them. It’s always good to get a reminder. Thanks. Always look for your posts.

    Reply
  2. Betsy Kurtenbach
    Betsy Kurtenbach says:

    Hello, I live in South San Francisco,Ca.
    And I love succulents have lots. We are getting lots of rain lately and I have been covering my plants with big garbage bags so they don’t get drenched! Am I doing the right thing to protect them from lots of dampens?? Thank you for your help❤️❤️

    Reply
    • Debra
      Debra says:

      Hi Betsy — Yikes! Big garbage bags? Not a good idea unless you’re using them somehow to make an umbrella. Think of it this way: What if you had a pet that for whatever reason was exposed to cold and rain and you wanted to protect it, but you couldn’t move it? You wouldn’t cover it with plastic! The poor thing needs sunlight and air circulation, and plastic holds in dampness—and besides, rain simply rolls off of it and soaks the ground anyway. Hopefully your pet succulent is growing in fast draining soil, atop a mound or berm, so its roots aren’t sitting in water. If not, topdress the soil with pumice, a crushed volcanic rock that absorbs moisture. If you have a patio umbrella with a concrete stand (so it won’t blow over), use it keep rain off the plant. But the bigger issue is what’s going on in the soil. Sodden roots are in danger of rotting.

      Reply
    • Perry
      Perry says:

      I live in SF near Daly City and it was suggested to me by Sloat Gardens to cover the more sensitive succulents with burlap. Many of my green aeoniums have had frost damage but almost all the others are fine! My soil is pretty sandy so the roots aren’t soggy, I assume South City soil is pretty similar?

      Reply
  3. Sarah Pearl
    Sarah Pearl says:

    Hi Debra, I just discovered your site and I love it…thank you. We live on Bainbridge Island, near Seattle, and our garden is going to be on the Garden Tour this year, so I’m trying to spruce things up a bit. I recently made a few succulent wreaths, including a horse head (I’ll post a picture to your FB page.) I used two heavy wire frames, lined the bottom one with coco fiber, sandwiched them together with sphagnum moss in the middle, tied them together, added another layer of moss on top (secured with fishing line) then planted. I sprinkled a bit of potting soil over the top to help hold the tiny ground cover “hair” in place.
    We are experiencing our typical NW 40-50 degree rainy weather right now, and I’m hoping to hang the wreath in early June, so it has lots of time to root and fill in. Shall I leave it outside in the rain (it’s elevated on little cups for drainage), assuming the temperature doesn’t drop below freezing, so should I bring it in under the eaves? Thanks!

    Reply
    • Debra
      Debra says:

      Hi Sarah — It probably would benefit from a gentle rain that soaks it thoroughly. There’s nothing like nitrogen-rich rain for boosting growth. But don’t let it get pounded, and bring it under cover when it gets sodden. Give it bright shade to half-day sun, and rotate it once a week for even growth and sun exposure. Either put it back out in the rain when it begins to dry out, or rehydrate the top few inches of moss with a watering can filled with collected rainwater. Once the plants have rooted, give them a boost with a dilute balanced fertilizer. I like Annie Haven’s Moo Poo tea, but the important thing to remember is to cut the strength by half (dilute half-and-half with water). If it hasn’t filled in by the tour, fill bare spots with cuttings held in place with U-shaped florist’s pins. (It’ll be our secret, ha.)

      Reply

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