The Four O’Clock flower (Mirabilis jalapa) hails from the tropical regions of the Americas, which means it’s definitely not a fan of the cold. While it’s often treated as an annual because it’s so frost-sensitive, here’s a pro tip: you can actually overwinter it! With a little care, this beauty can be a perennial staple in your garden.
What Makes the Four O’Clock So Special?
The Four O’Clock flower—botanically known as *Mirabilis*—comes in about 60 different species, and let me tell you, this plant absolutely loves the sun. When you find that perfect sunny spot, it rewards you with a lush explosion of blooms all summer long. True to its name, the flowers stay closed during the heat of the day and pop open in the late afternoon. They stay open through the night, filling the air with a lovely fragrance, before wilting the next morning—only to be replaced by a fresh batch of blooms by evening.
One of the coolest things about this plant is its color palette; you’ll often find different colored flowers blooming on the exact same plant! As summer winds down, the plant starts prepping for dormancy. It pulls all its nutrients from the leaves and stores them in its underground tuber. Once those nighttime temps start dipping below 50°F (10°C), it’s time to get that tuber tucked away for the winter.
How to Overwinter Your Four O’Clocks
The secret to the Four O’Clock’s survival is its tuberous root, which is very similar to a Dahlia bulb. To keep it alive for next year, you have to store it somewhere frost-free. Here’s how you do it:
- Once the leaves have turned yellow, use a garden fork to gently lift the tubers out of the ground.
- Shake off any loose dirt, but don’t wash them with water—you want to keep them dry.
- Trim off any remaining leaves and small feeder roots from the main tuber.
- Store the tubers on a wire rack or a wooden shelf.
- Alternatively, you can nestle them into a box filled with dry sand or sawdust.
- Move them to a cool, dry spot (around 40°F or 5°C is ideal).
- Every couple of weeks, give them a turn and check for any signs of rot or pests.
- If your indoor air is super dry, give them a very light misting of rainwater every now and then so they don’t shrivel up.
Once you see the tubers starting to sprout in the spring, you can pot them up in some good potting soil. Wait until early to mid-May—once the soil has warmed up and the threat of frost has passed—to move them back into the garden. Plant them about an inch (3 cm) deep in loose, nutrient-rich soil. Give them plenty of elbow room (about 20 inches apart) because these plants love to spread out! They also do great in patio containers; just make sure you add some broken pottery or gravel at the bottom for drainage, as they hate having “wet feet.”
