When grown in colder climates as an annual, it usually doesn’t get taller than 3 feet.
The bright green, leathery leaves grow to about 3 inches long in pairs up and down the stem.
The plant is popular with children for its recognizable scent that must be coaxed by touching the leaves.
The Spruce / Adrienne Legault
Check the label to be sure that you are indeed plantingSenna didymobotrya.
If the plant is getting too hot and dry, its leaves may close up during the day.
They also tend to close up at night to conserve moisture.
The Spruce / Adrienne Legault
Soil
This plant likes very fertile, rich, and well-drained soils.
When grown in pots, potting mix with some sandy loam is a good combination.
Potting mix alone may drain quickly and leave this moisture-loving plant too dry.
The Spruce / Adrienne Legault
Water
Water your tropical popcorn plant regularly.
Daily is the best bet if it’s in a container.
If the leaves close up during the day, that means it may be wanting some water.
The Spruce / Adrienne Legault
Keep the soil moist but not wet.
Misting the leaves with water in a sprayer is advisable if the weather is hot and dry.
This plant adores high humidity levels.
Fertilizer
Popcorn plants respond well to fertilizer throughout the growing season.
For the amount to use, follow the product label instructions.
There’s no need for serious pruning.
The seed pods are several inches long and contain at least a dozen seeds each.
Terracotta is an excellent choice as its porous walls allow moisture to evaporate.
It can also help to add a layer of pebbles to allow the water to drain even further.
To plant it outdoors, wait until all danger of spring frost has passed.
Overwintering
Popcorn plants can be overwintered if kept indoors.
A greenhouse is preferable, but a garage is fine if the temperature stays above 40 degrees Fahrenheit.
They will only need watering occasionally.
If kept in a dark place the plant will go dormant.
If you are in a tropical zone, overwintering plants in the garden should not be an issue.
This plant can also experience fungal diseases if kept too wet.
Avoid this by giving it excellent air circulation and keeping the soil moist, but not wet.
Popcorn plants should bloom readily in their proper climate zone.
When other plants wilt in the heat, the popcorn plant flourishes.
As a tropical plant, blooms can be severely stunted if the temperatures drop below 40 degrees Fahrenheit.
After flowering for a long season, the plant puts out brown seed pods.
Bloom Months
Popcorn plants typically bloom in late summer into fall, between July and September.
What Does Popcorn Plants' Flowers Look and Smell Like?
The popcorn plant’s vibrant coloryellowmakes it a dramatic sight in the summertime garden landscape.
Many say their scent is extremely similar to buttered popcorn.
These are tropical plants, so give them full sun on the hottest windowsill you could find.
They also need good air circulation, so a room with a ceiling fan is ideal.
Be sure to mist the plant regularly.
These plants are very susceptible to frost.
Senna didymobotrya (African senna).
CABI, Invasive Species Compendium.
Plant profile: popcorn plant.
Minnesota State Horticultural Society.
University of Florida, Center for Aquatic and Invasive Plants.
