Growing Merry Christmas Begonias

Variety: Begoniaceae
Cultivar: None
Zones: 10 to 11
AHS Heat Zone: Not defined for this plant
Soil Type: Well drained soil
Soil pH: 6.1 to 7.5
Sunlight: Partial shade to sun
Watering: Light watering
Fertilizer: Water-soluble, quick-release fertilzer
Availability: Sold as live, potted plants. Look for healthy, compact plants free of blooms.

When to plant: Merry Christmas Begonia is a perennial and can be planted in either the spring or fall, though it prefers spring planting, since it likes humidity and does not like the cold. While not drought tolerant, it does not like a lot of watering.

Planting Method
If you are going to use the Merry Christmas Begonia as an outdoor shrub, make the planting hole twice the size of the root ball. It should be deep enough to cover the plant just a tad higher than the soil line on the plant in the pot. This plant likes peat, so amend the soil with peat and fill the hole with the amended soil. If the plant came wrapped in burlap and the burlap is natural, you can just undo the burlap at the top of the plant and place the plant, burlap and all, into the hole. Fold the top of the burlap down so that it gets completely buried. Water the plant well from the bottom. Try not to splash a lot of water on the leaves.

If you going to plant the Merry Christmas Begonia in a container, make sure the container is big enough to allow for two years of root growth. Use a container with drainage holes, as this plant needs to be watered from the bottom. Once transplanted into a larger pot, water well from the bottom of the pot.

Watering
Water every 10 to 14 days. Use tepid, room-temperature tap water, as this plant does not like cold water, which tends to shock the roots. Pour the water in the water-catch bowl under the planter. After 15 minutes, pour any excess water out, as sitting water tends to attract pests and disease.

Fertilizing
Fertilize once every 14 days with a water-soluble, quick release fertilizer. You may also use an organic fertilizer, though it is not recommended for this plant. If you do use an organic fertilizer, be sure to follow the instructions on the package, as different organic fertilizers have different ingredients and strengths. Fertilizers should have a good combination of nitrogen and potassium for the best flowering and foliage growth.

Production
Merry Christmas Begonia grows large, bright-red leaves with green borders and showy pink flowers. The red color deepens toward the center of the leaf.

Diseases

• Powdery Mildew: Powdery mildew is a fungus that usually affects plants that have low air circulation and inadequate light. It is a bigger problem in the early spring and fall months, when the temperatures swing from high during the day to low at night, especially in zones with a lot of humidity. Powdery mildew forms a white or gray coating on the top of the leaves, making them turn yellow, curl up and drop off. It also causes stunted fruit that drops early. To control powdery mildew, decrease watering, use a fertilizer that is low in nitrogen and keep water off the foliage. Apply fungicides as directed.
• Rhizactonia Root and Stem Rot: Rhizoctonia is found in a lot of soils. It enters the plant through the roots and causes it to wilt as it travels up the stems. The lower leaves will wilt first. If you think your plant has this problem, decrease watering. If all of the leaves are wilted, discard the plant and clean the pot with a bleach-and-water mixture. Fungicides will also control Rhizactonia.
• Sooty Mold: Sooty mold is a black, sticky fungus that feeds on honeydew put out by aphids, mealybugs and scale insects. It attracts ants. You can get rid of it by keeping the pests out of your plants and by washing away with a sprayer. Though it is a fungus, fungicides may not control it. Be sure to keep the plant properly pruned to help with sooty mold.

Pests

• Scale Insects: The 1/8-inch-long scale insect attaches itself to the leaves and stems of plants. While the males have wings, the females do not, and spend their lives attached to the plant, sucking out juices with their piercing mouth parts. The scale insect excretes honeydew, which causes sooty mold that attracts ants. Cut any infected leaves off the plants. If the stems are also infected, you may have to dispose of the entire plant. You may be able to control them with insecticidal soaps or pesticides. You can also introduce parasitic wasps to your garden, as they are the scale insect's natural enemies. Lady beetles are also natural enemies.
• Spider Mites: Spider mites are tiny, eight-legged insects that feed on foliage, causing stippling, a distinctive spotted look on the leaves. They also create a thin web on the plants, and will use the web to move from one plant to another. Adults live up to 21 days and lay hundreds of eggs, which hatch in two to four days. You will probably need a magnifying glass to see the adults, eggs and nymphs. The adult will have two distinctive black spots on it. Spider mites tend to become immune to pesticides, so if you decide to use them, rotate the type of pesticide you use. Natural predators include predator mites, pirate bugs and lady beetles. Isolate plants infected with spider mites to stop their spread.
• Thrips: Out of the 6,000-plus species of thrips, there are five that like to visit garden plants. These narrow-bodied insects are about 1/8-inch long and have a life span of about 45 days. They are commonly found eating foliage, including the stems of plants. They do not like cooler temperatures and will invade a warm greenhouse. Keep plants well-weeded and use sticky strips to trap thrips. Some pesticides may work, though some only kill the larvae, not adult insects. Natural enemies include lacewings, ladybeetles and pirate bugs.
• Whiteflies: Whiteflies are less than 1/8 of an inch long, with white wings and yellow bodies. Their eggs hatch in 8 to 11 days. They have piercing mouthparts and suck the juices from plants, which causes stunted growth and yellow leaves. They can be controlled with pesticides, but in order for them to be effective, the underside of the leaves must be treated. Parasitic wasps and lady beetles can be used for outdoor control.

Cleanup
Prune Merry Christmas Begonia by pinching the stem tips of the plant. Pinching the stem tips will encourage the plant to bush out, which is perfect for container plants. If the plant is being used as a shrub or outdoor landscaping, prune for dead and decaying wood in the spring and throughout the growing season as needed.

Saving Seeds
This begonia reproduces through creeping rhizomes that produce babies. Babies can be cut and planted in soil amended with peat. Once the plant is established, it can be transplanted to a larger container.