These tuberous-rooted plants produce slightly pointed oval leaves on branching stems and reach 2-3 ft. tall and wide.
They get their common name because of the way they bloom.
This is a fast-growing plant that often sprawls in the garden and thrives in full sun.
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Four o’clock plant seeds can be sown directly in the garden once frost has passed.
If there is still a threat of frost, start 8 weeks before the last frost date indoors.
Plant in full sun and well-draining, acidic soil.
The Spruce / Evgeniya Vlasova
Soak the seeds overnight before planting to increase chances of germination.
However, these plants can grow in a variety of soil types.
Plants grown in containers will generally need more regular watering than those in the ground.
The Spruce / Evgeniya Vlasova
Temperature and Humidity
Consider your climate and planting location when planting four o’clock plants.
Humidity typically isnt an issue for them as long as adequate soil moisture is maintained.
Propagating Four O’Clock Plants
It’s possible to propagate four o' clock plants by cuttings.
The Spruce / Evgeniya Vlasova
Replant them the following spring once temperatures are reliably above freezing.
If you live within the plant’s growing zones, the tubers can stay in the ground for winter.
Common Pests & Plant Diseases
Four o’clocks tend to be very pest- and disease-resistant.
The Spruce / Evgeniya Vlasova
However, rusts (white rust and brown rust) and some leaf spot diseases can affect the foliage.
What Do Four O’Clock Plants Flowers Look and Smell Like?
The tubular flowers have a lemony-sweet fragrance.
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Some four oclock plants produce bicolor flowers, sometimes with marbling or other markings.
However, some common issues can arise in subpar environments.
So your plant may still bloom overnight; you just don’t see it.
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Very nutrient-poor soil also can result in sparse blooms.
Have asoil testdone to verify your soil has enough phosphorus, which aids in flowering.
Yes, hummingbirds like four o’clock flowers.
The plant will attract them in the late afternoon/evening when the flowers open.
The best companion plants for four o’clock plants include lantana, summer phlox, zinnias, and morning glorys.
Four O' Clock.Utah State University.
