How to Grow Four O'clock Flowers

About Growing Annual Four O'clock Flowers in Your Home Garden

My Grandfather loved growing Four O’clock flowers. They were his favorite. He enjoyed the bright trumpet-shaped flowers, which attract Hummingbirds. Annual Four O’clock plants got their name because their blooms open in mid-afternoon. It remains open overnight and closes in the early morning. They will also remain open on cloudy days. They are also noted for their strong, pleasant fragrance.

Native to tropical areas of North and South America, they are also called the “Marvel of Peru”. Aztecs in Mexico were the first to cultivate them. Four O’clocks are actually perennials that are grown as annuals, in most areas of the U.S.

The bushy plants make attractive hedges or borders. Flower colors include white, red, pink, yellow, and some two-toned blooms. Because the flowers are open late in the day and early evening, we recommend you place them in areas where people will see them in the late afternoon to early evening hours.

Grow them in flower beds, borders, around patios and walking paths, or in containers.

When blooming, the sweet scent of the flowers attracts pollinators. And best of all, the tubular flowers attract hummingbirds, too!

Night Bloomers: How many flowers do you know of are open in the evening? See Moonflowers

Four O'clock Plant Specifications

Flower Colors: Pink, magenta, red, yellow, and white flowers are most common. Also, there are many other less common colors.

Flowers Bloom: Summer through Fall. The plants have a log blooming period.

Plant Height: 1 to 2 feet

Light Requirements: Full sunlight to partial light.

Ideal Soil pH: 6.0 – 7.0.

Hardiness Zone: 9 – 11.

Toxicity: Yes.

Deer Resistant? Yes. Deer do not like their bitter taste or their scent.

Number of Species: 45

Native To: South America.

Plant Type: Herbaceous perennial, usually grown as an annual.

Botanical Name: Mirabilis Jalapa

Other Names: Marvel of Peru, Garden Jalep

Are Four O'clock Plants Edible?

NO!!

All parts of the Four O’clock plant are poisonous to humans and pets.

The seeds look similar to peppercorns. However, the seeds are highly poisonous.

Gardeners should wash their hands after handling the plant or seeds.

Medicinal Applications for Four O'clock Plants

Native American tribes have used Four O’clocks for ages to treat a variety of ailments. It is popular for home and herbal medicinal applications. Here are some of the medicinal uses:

Important Note: Because all parts of this plant, including the seeds, are poisonous, do not use this plant for medicinal purposes unless you are well aware of how to prepare and use it.

Use it for skin infections and imflamation.
It is used to treat digestive disorders.
Treat insect bites.

Light Requirements

Grow Four O’clock flowers in full sun. They grow their best with six or more hours of direct sunlight.

The plants also grow in light or partial shade. However, the plants can get leggy. And, they will have fewer blooms.

Annual Four O'clock Plant Propagation

Four O’clock plants are typically grown from large seeds. As a result, they are easy to handle and to plant. Four O’clock seeds germinate quickly, and grow fast, up to 2-4 feet.

Keep the seed bed moderately moist during germination.

Plant Four O’clock seeds directly into the garden, just before the last frost in your area. Cover seeds with 1/4″ of soil. Space plants 12 inches apart and thin to two feet apart.

In addition, Four O’clocks can be propagated by its tubers. Tubers should be dug up in the fall and stored in the dark, in damp peat moss or sand.

Days to Germination: 10 – 15 days.

How to Grow Four O'clock Flower Plants

The plants are excellent re-seeders. So, pick a planting location where they can grow undisturbed for many years.

Four O’clock plants prefer full sun but will tolerate partial shade. Note that in the partial shade, they may grow lanky. So, pick a planting location where they can grow undisturbed for many years.

They will do well in rich, well-composted soil as they are big eaters.

Keep soil moist, not wet. The plants can suffer root rot in extended periods of wet soil.

Add a general-purpose fertilizer once or twice a month to encourage vigorous growth.

Keep the area well weeded while the plants are young. Then, apply a thick layer of mulch for a neat and tidy appearance.

Collecting seeds for next year is easy. Gather the FOur O’Clock seeds when the pods are dry-looking. The large seeds are easy to handle. Separate the seed from the pods. Then, allow the seeds to dry on a screen before storing them for next year.

Four O’clock fit well in borders, as small hedgerows. Try growing them around your mailbox. But, the best place to grow them is where you can see them from a window or the deck and watch the hummingbirds at work feeding on the nectar.

Growing Four O'clock Flowers in Containers and Flowerpots

Four O’clock flowers are great candidates to grow in containers or flowerpots on your patio or deck. Like other container plants, they require a little extra attention than when planted in the ground.

Use flowerpots or containers with drain holes in the bottom. This allows excess water to drain so the roots will not rot.
Keep an eye on the moisture level. Check the plants every day or two, especially in extended periods of hot, dry weather. Keep the soil moist, but not wet. It is okay to let the top of the soil begin to dry between watering. When watering the plants, thoroughly wet the soil. Excess water will drain through the hole in the bottom of the flowerpot.
Nutrients in a flowerpot are limited. So, use fertilizer spikes to feed the plants. Or, apply a light solution of liquid fertilizer every 2 – 4 weeks.
Move the flowerpot around, as needed to give the plants optimum sunlight. They are resilient in hot weather and direct sunlight.
Keep them well-trimmed. They are more visible on a patio or deck. So, you want them to look their best.

Pruning Four O'clock Plants

When the young plant has reached several inches tall, pinch back the growing tip. The plant will produce multiple new shoots and become busier. The plant will reward you for this pruning by producing more flowers.

Remove any dead or sick leaves and branches during the growing season.

In mid-summer’s heat and after the first set of blooms, the plant may start to look a little ragged. Cut back the plant by one-third. This causes the platn to grow more new leaves and branches. And, it rewards you with new blooms.

Insects and Plant Disease

Insect and disease problems are uncommon for Four O’clock flowers. If problems occur, treat early with organic or chemical insect repellents and fungicides.

Root rot can occur in prolonged periods of wet soil.

Also see: Plant Problems – Identify the causes and find the cures.