Mother Nature originally designed the Moss Rose (Portulaca grandiflora) in South America, where “winter hardy” isn’t exactly a requirement. She probably didn’t realize that we gardeners in cooler climates would fall head over heels for its vibrant blooms! So, what’s a gardener to do? Should you treat it as an annual or try to keep it alive through the winter?
Outdoors, Moss Rose is strictly an annual
No matter how sheltered your garden spot might be, a Moss Rose isn’t going to survive a typical winter outdoors in our neck of the woods. Even the best protective covers won’t do much; the slightest frost will freeze the sap right in its “veins.” Because of this, it’s almost always grown as an annual outside. Unless you happen to have a freakishly frost-free winter, don’t expect it to pop back up on its own.
New life through self-seeding
Every now and then, you might spot a Moss Rose peeking out in the spring right where one grew the year before. It’s tempting to think it “survived” the winter, but usually, you’re looking at a brand-new plant that sprouted from seed. The seeds are incredibly tough—they can handle the cold and stay viable for up to four years! You can even collect these seeds yourself and start them indoors around March. By the time May rolls around, you’ll have sturdy little starts ready for the garden, giving you a head start on those beautiful blooms.
Pro Tip:
Only leave a few spent flowers on the plant if you’re planning to collect seeds. Pinch off the rest regularly (deadheading) to encourage the plant to keep pumping out new buds.
How to successfully overwinter your Moss Rose
If you’re really attached to your plants, it is possible to overwinter this non-hardy beauty, but you’ll need a frost-free indoor spot. Obviously, the plant needs to be in a pot. If you’re planning on bringing it inside, it’s easiest to grow it in a container from the start. However, you can also carefully dig up a garden specimen and pot it before the first frost hits.
- Bring it inside well before the first frost.
- Find a bright, cool room.
- Temperatures between 60°F and 65°F (15-18°C) are ideal.
- Keep care simple: just a little water every now and then.
- Skip the fertilizer during the winter months.
- Move it back outside in mid-May.
- Give it some time to acclimate to the direct sun again slowly.
Moss Rose vs. Purslane
Sometimes people get Moss Rose confused with common Purslane or Winter Purslane. While both of those are often grown as leafy greens, the Moss Rose is primarily an ornamental flower. Technically, Moss Rose is edible, but it doesn’t taste nearly as good as its cousins. Just like the Moss Rose, summer purslane can’t handle the cold, while winter purslane is a total champ in freezing temperatures.
