Plectranthus 1c Copenhagen Bot Garden 121205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus 2b Grootvadersbos, Western Cape, South Africa 100922 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus 2c Grootvadersbos, Western Cape, South Africa 100922 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus 4 Lund Bot Garden 120918 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus ernstii 6 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus ernstii 7 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus hardiensis var tomentosus 1 Lund Bot Garden 120911 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus hardiensis var tomentosus 2 Lund Bot Garden 120911 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus madagascariensis 2 Harold Porter Bot Garden, South Africa 160926 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus madagascariensis 3 Harold Porter Bot Garden, South Africa 160926 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus parviflorus 4 Olinda Endangered Plant Facility, East Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus 1a Copenhagen Bot Garden 121205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus 1b Copenhagen Bot Garden 121205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus 2a Grootvadersbos, Western Cape, South Africa 100922 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus 3 Aloe forest, Nieuwoudtville, Western Cape, South Africa 011017 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus argentatus 1 Lund Bot Garden 081103 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus argentatus 2 Lund Bot Garden 081103 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus argentatus 3 Lund Bot Garden 081103 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus argentatus 4 Lund Bot Garden 081103 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus argentatus 5 Lund Bot Garden 081103 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus ernstii 1 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus ernstii 2 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus ernstii 3 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus ernstii 4 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus ernstii 5 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus madagascariensis 1 Harold Porter Bot Garden, South Africa 160926 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus neochilus 1 Kirstenbosch 100916 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus neochilus 2 Kirstenbosch 100916 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus parviflorus 1 Olinda Endangered Plant Facility, East Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus parviflorus 2 Olinda Endangered Plant Facility, East Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus parviflorus 3 Olinda Endangered Plant Facility, East Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus saccatus 1 Kirstenbosch 100916 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus saccatus 2 Kirstenbosch 100916 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus zuluensis 1 Lund Bot Garden 070625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Plectranthus zuluensis 2 Lund Bot Garden 070625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).