The moonflower is a vining, tropical perennial often grown as an annual. Botanically known as Ipomoea alba, moonflower has heart-shaped, green foliage and produces large, white, fragrant flowers. The delicate 5- to 6-inch blooms open in the afternoon and close up by morning. Though moonflower blooms are short-lived, with each flower only lasting one night, the plant is a vigorous grower and produces an abundance of blooms throughout the late summer. Moonflower plants are generally not sold at plant suppliers or nurseries, so growing them by seed is often your best option. Properly prepared seeds tend to germinate readily.
Vigorously rub each moonflower seed with the sand paper until a small portion of the shiny, outer protective coating appears to be penetrated. Place the seeds in the jar and add warm water until they are submerged. Let the seeds soak for 24 hours.
Cultivate the planting bed with a shovel to a depth of 8 to 12 inches. Break up any dirt clods and remove existing weeds. Add a 2-inch layer of compost and work it into the soil. Level the soil with a hand trowel.
Place the moonflower seeds on top of the soil, spacing them 3 inches apart. Gently press the seeds 1/4 inch into the soil. Cover them with a small amount of dirt and pat it down.
Mark the planting area by inserting several wooden craft sticks next to the seeds. The craft stick markers will help you identify the seedlings once they emerge.
Water the area well and keep the soil moist, but not soggy. Expect seedlings to appear in about a week.
Wait until the soil’s temperature has reached 65 degrees Fahrenheit or higher before planting moonflower seed. If conditions are too chilly outside, plant seed indoors in potting soil and place them in a bright window. Move plants outdoors as soon as temperatures warm.
Moonflowers are rapid growers that quickly sprawl. They require a trellis, arbor, fence, tree or other large structure on which to grow.
Moonflowers can also be grown in large containers. Use a rich, well-draining potting soil and be vigilant about watering, as container-grown plants dry out more quickly than those grown in the ground.
The moonflower is considered invasive in some parts of the country. Before planting, check on the moonflower’s status in your area with the local Agricultural Commissioner’s office.