You’re aware that it’s death to succulents to overwater them, but did you know that under certain circumstances, they can handle much more rain than they need? It's something I've observed for years in my own garden.
Because succulents growing at the top of a steep slope get excessive amounts of rain every winter, I've worried they might drown or rot. Sporadically, these dozen or so fat-leaved plants get significantly more water than similar specimens elsewhere in the garden---at least 100 times as much, and that's conservative.
It's because they're directly beneath a gutter that overflows during cloudbursts, sending a rooftop of rain directly onto them. This winter wasn't the first time that's happened, but it was likely the most in terms of quantity. In the past, my slope-top succulents continued to grow---even thrive---despite being deluged.
The winter waterfall
The roof gutter overflows 20 feet above the plants. After drenching them, the water flows and filters into the lower garden. The gutter doesn't need fixing, so every year I merely observe it, and every year I wonder how long the succulents beneath it can tolerate it.
Similar to their native habitats, the area’s small- to medium-sized aloes cling to what likely feels to them to be a "cliff." Soil along the top is coarse, pebbly and shallow. Several years ago, to keep the soil from washing away, I piled pieces of broken pottery around the plants. That did not, however, slow or minimize the intensity or quantity of the winter waterfalls.
This week, aloes and several other types of succulents at the top of the slope got pounded, but they're doing fine. The reason can only be superb drainage. Although their roots are continually wet, succulents in that spot never sit in a puddle. It makes sense that as long as water drains rapidly, succulent roots won't drown or rot!
Assessing the Damage
So yet again my aloes are fine despite downpours. However I did lose a venerable potted Euphorbia obesa. There's no excuse. I should have moved it under cover. Vinnie, a newsletter subscriber in my area, lost a pachypodium. Such bulbous-trunked succulent trees can rot fast. Like barrel cacti, one day the plant's fine; the next, a spiky, goopy husk.
I don't know about you, but I'd rather have my phone blare "hail in 20 minutes!" than a flash-flood warning. (But then, I'm alongside a canyon, not IN one.) Hail is infuriating---it's sudden, and it causes pitting on leaves that takes plants months to replace with new growth. Except aloes. What IS it about aloe leaves? They're brittle but don't show damage from impact.
What to do
Find out how I protect my vulnerable succulents before storms, and how I check them for rot and other damage afterwards: