How to Grow Petrocosmea - Planting & Caring

By Sharon & Team   /   Herbaceous Category   /   2023

Petrocosmea, also known as Chinese violet or jewel orchid, is a genus of about 60 species of flowering plants in the family Gesneriaceae, native to China, India, Myanmar, Thailand, Laos, Vietnam, and Malaysia. They are herbaceous perennials with opposite leaves and small, bell-shaped flowers borne in terminal racemes or panicles.

How to Grow Petrocosmea - Planting & Caring

Growing Easiness

Is it easy to grow Petrocosmea plant? Because it requires warm and humid conditions to grow, it is not an easy plant to take care of.

Plant Size

How big can it be? Since they are small, most grow in pots or hanging baskets. The average size of a Petrocosmea is 5 to 12 cm in diameter, but some can get as big as 20 cm. The plant's leaves are dark green with light green or white veins. They are oval-shaped with slightly serrated edges and grow in opposite pairs on the stem. The flowers of the Petrocosmea are white or pale pink and have four petals. They bloom in the summer and are about 2 cm in diameter.

Growth Rate

How fast is the growth? known as the kousa dogwood, is a small to medium-sized, deciduous flowering plant native to eastern Asia. The plant is most often found in woodland habitats, where it can form large colonies. The kousa dogwood has a slow growth rate and can take up to 10 years to reach its full height of 15–25 feet. The plant's leaves are ovate-shaped and measure 2–4 inches long. The kousa dogwood produces small, white flowers that bloom in late spring or early summer. The flowers are followed by spherical, red fruits that ripen in late summer or early fall. The kousa dogwood (Petrocosmea) is a small to medium-sized deciduous flowering plant native to eastern Asia. The plant is most often found in woodland habitats, where it can form large colonies. The kousa dogwood has a slow growth rate and can take up to 10 years to reach its full height of 15–25 feet. The plant's leaves are ovate-shaped and measure 2–4 inches long. The kousa dogwood produces small, white flowers that bloom in late spring or early summer. The flowers are followed by spherical, red fruits that ripen in late summer or early fall.

Petrocosmea Basic Knowledge

Plant Form Herbaceous
Family Gesneriaceae
Origin China

Lifespan, Perennial or Annuals

How long is the lifespan? Although most Petrocosmea species are annuals, a few are short-lived perennials, continuing to bloom for several years with proper care.

Ideal Temperature

What is the ideal temperature? The plant prefers cool temperatures from 50 to 77 degrees Fahrenheit. The maximum temperature it can tolerate is 86 degrees Fahrenheit, and the minimum is 41 degrees Fahrenheit. At high temperatures, the plant needs increased humidity in the air.

Humidity

What about the humidity? The plant does best in high humidity, so you should not spray it with water. Instead, you should put the pot in a tray with wet pebbles.

Light Requirement

What amount of light this plant needed? Common ly known as the Gesneriad family, the petrocosmea is a diverse bunch of flowering plants that are typically found in tropical and subtropical regions of Central America. Many of these plants are known for their brightly colored flowers, which make them popular choices for gardens and indoor pots. One of the most popular Gesneriads is the petrocosmea, which is a scrambling or climbing plant that can reach up to 3 meters in length. The petrocosmea is a low-maintenance plant that is suitable for east, west, and north-facing windows. It is also one of the Gesneriads that is least demanding in terms of lighting conditions. The main condition for petrocosmeas grown in insufficient lighting is to turn the plant regularly so that it evenly forms. Petrocosmeas also grow easily under conditions of artificial illumination for 12 hours a day, with lamps placed at a height of 12 cm above the plant.

Soil Composition

What is good soil for Petrocosmea? Sometimes, it is difficult to find the right kind of soil for your plants. If you have a Petrocosmea, you should mix 1 part garden land, 1 part coarse-grained sand or perlite, 1 part wet peat or humus (leafy earth), and a little bit of lime. You can also mix peat, perlite, and vermiculite in equal proportions. It is also mandatory to use drainage.

Watering Time

How much I must water Petrocosmea? So, water the plant regularly, but be sure that the top layer of the soil dries slightly. Watering by immersion is also an option, and is especially recommended if the plant has grown and the leaves cover all the soil in the pot. Remember to use only soft water that is at room temperature. Another option for watering is wick watering.

Fertilizing and Nutritient

About fertilizer. While your Petrocosmea is actively growing, from spring to autumn, once a month, apply a liquid fertilizer, diluted two-fold. An organic fertilizer such as fish emulsion or seaweed extract is ideal. If you grow your plant indoors, be sure to leach it monthly with clear water to prevent the build-up of fertilizer salts in the potting mix.

Reproduction

How to reproduce Petrocosmea? Unless you have a mature plant to take cuttings from, you'll have to start with seeds. Petrocosmea readily self-sows, so if you have a plant, it's easy enough to collect the seeds. Just let the flowers go to seed, then wait a few weeks until the seed pods turn brown and split open. Seeds should be sown in late winter or early spring. Surface sow the seeds onto moist, well-drained seed-starting mix and press them gently into the mix. Do not cover the seeds as they need light to germinate. Place the seed tray in a warm spot out of direct sunlight and keep the mix moist but not soggy wet. Seeds usually germinate within 2-4 weeks. Once seedlings are large enough to handle, transplant them into individual pots. Use a good quality potting mix that drains well. Water Petrocosmea plants regularly during the growing season, allowing the top couple of inches of soil to dry out between waterings. Fertilize monthly with a balanced fertilizer such as 10-10-10.

Bloom

Why Petrocosmea won't bloom? The reason I'm interested in this plant is the shape of the flower. The flowers are blue and campanulate shaped. What does campanulate mean? It means that the flowers cup or bell shaped. The flowers are also on long peduncles.

Transfer or Repotting

How much I must water Petrocosmea? The plant does not like too frequent transplants, it is necessary to transplant it once in 2 years. The maximum diameter of the pot for the largest species is 12-13 cm, most types of suitable size are about 7.5 cm. To transplant the plant, it is necessary to place it under a polyethylene package for the best survival. Some growers practice constant fertilization of the substrate and its periodic washing with water to remove excess salts. In this case, transplantation can be less frequent, because the plant does not like to be disturbed by its root system.

Caring The Petrocosmea

How to care the plant? known that the plant is unpretentious, so it is often grown at home. Petrocosmia refers to perennial herbs of the Gesneriaceae family. The homeland of the plant is South Africa. In the natural environment, it can be found in the mountainous areas of Lesotho. The height of the bush can reach one and a half meters. The leaves are large, dark green in color, with a purple or red reverse side. The flowers are rather small, tubular, painted in purple, white or pink colors. Blooming petrocosmia lasts a long time - from spring to autumn. To care for a petrocosmea at home, it is necessary to provide the plant with good lighting, but direct sunlight should be avoided. The optimal air temperature for comfortable growth and development is + 18 ... + 20 degrees. It is necessary to water the flower moderately, as the root system is located close to the surface of the soil. The soil for planting should be loose, breathable and nutritious. It is necessary to feed the petrocosmia twice a month with complex mineral fertilizers. It is necessary to ventilate the room regularly, as the plant does not tolerate stagnant air. The plant is propagated by cuttings or seeds.

Pests & Challenges

What is the challenge when caring Petrocosmea plant? Sometimes, the plant is affected by spider mites, mealybugs, thrips, whiteflies. To prevent the appearance of pests, the plant is useful to ventilate. It is possible to decay the roots of the plant with excessive watering when growing in heavy soil. When water hits the leaves, yellow spots form on the sun.

Toxic & Poisonous Type

Are Petrocosmea poisonous? The plant is a member of the Gesneriaceae family and is native to China. The plant has been used in traditional Chinese medicine for centuries. The plant is toxic to humans and animals and can cause death if ingested. The plant is also known to cause skin irritation and should be avoided by people with sensitive skin.