Aesculus 2a Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus 2c Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus 2d Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus carnea 1 (cult) Lund Sk 070505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus carnea 4 (cult) Lund Sk 120530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus carnea 5 (cult) Lund Sk 120530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus carnea 6 (cult) Lund Sk 120530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus carnea 7 (cult) Lund Sk 120530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus flava 1 Copenhagen Bot Garden 140515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus flava 2 Copenhagen Bot Garden 140515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus flava 4 Copenhagen Bot Garden 140515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus flava x sandra 1 Flinck's Garden, Bjuv Sk 070521 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus glabra 2 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus hippocastanum 1 Borlunda Sk 080515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus hippocastanum 2 Dept of Botany, Stockholm University 060524 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus hippocastanum 4 (cult) Lund Sk 080523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus hippocastanum 5 Dept of Botany, Stockholm University 060821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus hippocastanum 6 Dept of Botany, Stockholm University 060821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus hippocastanum 7 Lund Bot Garden 130909 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus indica 2 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus indica 3 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus indica 4 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus indica 5 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 3 Copenhagen Bot Garden 130807 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 4 Copenhagen Bot Garden 130807 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 5 Copenhagen Bot Garden 130807 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 6 Copenhagen Bot Garden 130807 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 7 Copenhagen Bot Garden 130807 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 9 Copenhagen Bot Garden 130913 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 1 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 4 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 7 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 8 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus 1a Copenhagen Bot Garden 130625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus 1b Copenhagen Bot Garden 130625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus 1c Copenhagen Bot Garden 130625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus 2b Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus carnea 2 (cult) Lund Sk 120530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus carnea 3 (cult) Lund Sk 120530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus flava 3 Copenhagen Bot Garden 140515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus flava x sandra 2 Flinck's Garden, Bjuv Sk 070521 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus glabra 1 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus hippocastanum 3 (cult) Lund Sk 080523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus indica 1 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 1 Copenhagen Bot Garden 130807 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 2 Copenhagen Bot Garden 130807 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus parviflora 8 Copenhagen Bot Garden 130913 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 2 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 3 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 5 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus pavia 6 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus x hybrida (A flava x pavia) 1 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Aesculus x hybrida (A flava x pavia) 2 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).