Black-eyed Susanne, Thunbergia – sowing and care

The black-eyed Susanne is a climbing plant and grows slightly herbaceous, but with lush, 10 to 30 cm long, overhanging flowering shoots. It is also popular as a hanging plant. Their shoots can grow up to 4 cm thick. When wintering indoors, the plant has foliage all year round. Otherwise, the leaves freeze off with the first frosts, since the black-eyed Susanne is not hardy in European latitudes. The shape of its light green, slightly hairy leaves is triangular to heart-shaped. The leaves, which do not show autumn color, can grow up to 7 cm long and up to 3 cm wide.

flowers and seeds

From the beginning of June to the end of October, the black-eyed Susan produces numerous flowers with optimal care. The approx. 2 to 5 cm large flowers have a black spot in their throat, which forms a wonderful contrast to the rest of the yellow, white, orange or brown color of the flowers. Black-eyed Suzanne seeds are a type of winged capsule.

Popular Varieties

The most popular is the variety with lemon yellow flowers and a real black eye.

Other varieties:

• Thunbergia alata Bakeri – without an eye with white flowers
• T. alata Dodsii – with brownish flowers
• T. alata Aurantiaca – with orange flowers

The optimal location

Black-eyed Susanne likes a bright, warm, sunny and airy spot in the garden, which also offers sufficient protection against wind and bad weather. The Thunbergia can also stand in the light penumbra on the balcony, but must also be protected. Black-eyed Susanne doesn’t get along very well with wind, rain and cold. She will grow in such a location and has beautiful green leaves, but will produce little or no flowers. The soil should be rich in humus and loose. It must not dry out. Both in the garden and on the balcony, do not forget that the beautiful flowering plant needs a climbing aid or a hanging basket, depending on your taste. The plant will thank you and transform your little flower kingdom into a sea of ​​blossoms.

Planting and care of black-eyed Susanne

The black-eyed Susan feels particularly well in a nutrient-rich and loose soil. Compost mixed into the soil is sufficient as a nutrient base. Of course you can also use horn shavings if you don’t have a compost substrate available. Horn shavings are always a good alternative. Fine gravel or sand is used to loosen the soil or substrate in the bucket or pot. It is best to place a few pieces of pottery shards in the drainage hole of the bucket so that it does not become blocked with soil. If the drainage hole in the pot or tub is clogged, waterlogging can occur. Black Susanne can’t stand this!

Watering and fertilizing:

• Fertilizing regularly helps to produce numerous blooms.
• Give organic fertilizer every two to four weeks.
• Ordinary fertilizer can also be used.
• Water regularly.
• Avoid waterlogging.

Remove withered flowers

Like every climbing plant, the Black Susanne not only needs a sufficient supply of nutrients for a long and lush flowering period, but also daily attention. Thunbergia will only delight you with more blooms if you continually remove the old and withered blooms. You should also remove any seed pods that may have set in order to continue to strengthen the plant. In addition, the so-called pinching promotes plant growth and branching. The tips of the shoots are cut off to attract side shoots.

climbing aids

In order for the black-eyed Susanne to develop optimally and develop lush leaves and flowers, it is important that it can climb or climb down from hanging pots. If you use climbing aids, you will immediately realize that the Thunbergia is a very special climbing plant. Because it not only simply grows up and climbs up, but also winds its way counterclockwise up the trellis. It’s sort of a left winder.

multiply

Black-eyed Susanne is a climbing plant that is easy to propagate from seeds or cuttings. Both methods require patience and finesse.

Propagation by seeds

You can take the seeds from your own Thunbergia or buy them from specialist retailers. It is best to sow at the end of February or in early spring around the end of March so that you can plant the small plants in good time. The seeds are sown in seed trays with potting soil and covered with a layer of soil about 1 cm thick. After a few weeks, the seedlings are so large that they can be isolated. To do this, plant two to three plants in each pot. If you use larger plant bowls, keep the small groups of plants at least 40 cm apart. You can plant the young plants in larger pots or tubs and put them outdoors from the end of May at the earliest. But if late frosts occur, the tubs should be brought into the house overnight.

Propagation by cuttings

You can also propagate the black-eyed Susanne using head cuttings. This is the quickest and easiest way to propagate climbing plants. That’s how it works:

• Take the cuttings from January to March or from August to storing in the conservatory or overwintering place.
• Only cut off well-ripened shoots that are not yet lignified.
• It is best to use a good, sharp knife or sharp secateurs for this.
• Remove the leaves from the cuttings, but not completely.
• Rule of thumb: Leave three pairs of leaves per cutting.
• Now put them in a larger box or in small pots with permeable plant substrate.
• Optionally use perlite or sand to make dense substrate a little more permeable
• Water the cuttings lightly and place them in bright but not direct sunlight.
• Place loose foil over the cuttings in the box to prevent evaporation or small foil bags over the individual pots.

Cut and overwinter

The perennial black-eyed Susanne is not a hardy climber and must therefore be overwintered in the house or conservatory over the winter. However, the beautiful climbing plant is often treated like an annual plant, since in our latitudes it cannot remain in the garden all year round. But it is possible to bring black-eyed Susanne successfully through the cold season by allowing and trimming her.

You can safely cut the climbing plant back to about 50 cm with sharp pruning shears before it moves into its winter quarters. You can make up for the pruning after you have cleared the space or in early spring if you forgot to do it when you put it away.

But don’t wait too long before putting Black Susanne in, because even temperatures below 8 °C can cause problems for the heat-loving plant. Temperatures between 8°C and 12°C are favorable for the climate in the bright and frost-free winter quarters. During the hibernation you should not fertilize and only water a little. But make sure the soil doesn’t dry out. In between, you must not forget to look for pests that like to nest in the winter quarters. If the black-eyed Susanne is infested with pests, it is best to treat the plant quickly and place it in quarantine quarters.

Black-eyed Susanne may be in a brighter place as early as February, but definitely not on the balcony, terrace or in the garden. In the house in a brighter place, the plant now gets the warmth it needs to grow and thrive, so that you can enjoy numerous flowers again in summer. After the ice saints, you can put the beautiful climbing plant outside again. Before that, repotting is a good alternative to give the plants a growth spurt or if the pot or tub has become too small.

diseases and pests

In the winter quarters, the black-eyed Susan can sometimes be attacked by spider mites if the room air is too dry and warm. Aphids can also have settled, which were accidentally overlooked when clearing.

spider mites

Warm and dry air promotes infestation with the soft-skinned and eight-legged animals that like to lay their fine webs over the leaves and flowers. Like aphids, spider mites are sucking pests and prefer to attach themselves to the underside of the leaves. There they pierce the lower epidermis with their mouthparts and suck chloroplasts and the sugary cell sap out of the plant. This leads to the collapse of the attacked plant cells and to increased water absorption and increased transpiration. The affected leaves turn finely mottled and gradually become darker and grey-brown the longer the infestation lasts.

However, you can drive away the spider mites with simple means. You just have to use them continuously. For example, rinsing off the affected plants helps, preferably in the bath or shower. Regular spraying of the underside of the leaves with nettle or basil tea also helps. Neem oil or tea made from neem tree seeds also help. In well-stocked hardware stores and plant centers you can get ready-made preparations with neem tree that are non-toxic to humans and pets and very environmentally friendly.

aphids

The aphids, which are only a few millimeters in size, are black-brown, green or red-brown in color depending on the species and can be seen with the naked eye. They also like to live in groups on their host plants. Like spider mites, they also target the sugary plant sap and pierce the plant to do so. However, since they excrete a large part of the sugary juice, a sticky coating forms on the plant.

You can drive away the aphids with simple means as well as the spider mites. Either with yellow boards or with diluted soapy water, with which you regularly spray the affected leaves. This is particularly appropriate in the winter quarters. A broth made from cigarette butts is also useful. To do this, pour boiling water over cigarette butts and let everything steep for a few days. Then spray the affected parts of the plant with the finished broth. If your black-eyed Susanne is also infested with aphids outdoors in the summer months, you can use ladybirds. A single one eats up to 100 aphids a day.

Conclusion
The heat-loving black-eyed Susanne is a beautiful climbing plant for gardens, terraces and balconies. It is often only planted as an annual, although it can be overwintered very well. If it is not too cold and not too warm in winter, you will enjoy this pretty plant for many years and you can propagate it with seeds or cuttings. The different varieties with different colored flowers have the right plant for every lover.