How To Sow Black-Eyed Susan (Thunbergia Alata) Seed

How To Sow Black-Eyed Susan (Thunbergia Alata) Seed

Grow your own Thunbergia alata for a summer annual or winter houseplant

This is a vigorous climber which is usually grown as a summer annual and will quickly cover a trellis, usually growing to 120cm (4'). It can also be kept as a houseplant, and either trained up a tripod of canes or as a hanging plant in a basket. Sow in January/February for summer annuals or in summer for houseplants over the winter.


 You will need:

  • seed tray
  • compost
  • seed
  • Vermiculite
  • propagator
  • tray to hold water
  • labels

Soaking the seed for 24 hours before sowing will speed up germination but is not essential.

Fill the seed tray with good quality John Innes Seed compost.

Stand the tray in a tray of water and leave for 10 – 15 minutes until the compost is moist.

Sow the seed thinly on the surface and cover with a thin layer of Vermiculite, not compost, as they need the light to germinate.

Place in the propagator at a temperature of 20 – 25C (68 – 77F); they should germinate in 14 – 21 days.

Keep the compost moist but not sodden.

Prick out when large enough to handle.


Angela Slater

Daughter of a farmer and market gardener so have always had a connection with the outdoors, whether it was keeping animals or producing fruit, vegetables and cut flowers. Along with my work at Hayes Garden World I also have a smallholding, mainly breeding rare breed pigs. I gained an HND and BSc in Conservation and Environmental Land Management, as a result I am an ardent environmentalist and have a keen interest in environmentally friendly gardening. In my time at Hayes I worked for several years in the Outdoor Plant and Houseplant areas.