Hedyotis sp.

Hedysarum prostratum, and others

Helianthus angustifolius. sp. nova.

Heuchera

Hibiscus

Houstonia cœrulea, purpurea, and varians

Hydrangea glauca

Hypericum fasciculatum, nudiflorum, prolificum, and others

Hypnum sp.

Hypoxis erecta.