Families (As per The Plant List)

 
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | A-Z

H

Haloragaceae - 4 (Myriophyllum indicum, Myriophyllum intermedium, Myriophyllum oliganthum, Myriophyllum tuberculatum)

Heliconiaceae - 2 (Heliconia psittacorum, Heliconia rostrata)

Hernandiaceae - 1 (Gyrocarpus americanus)

Hydatellaceae - 1 (Trithuria konkanensis)

Hydrangeaceae - 1 (Hydrangea macrophylla)

Hydrocharitaceae - 11 (Blyxa aubertii, Blyxa echinosperma, Blyxa octandra, Halophila beccarii, Hydrilla verticillata, Najas graminea, Najas indica, Najas minor, Nechamandra alternifolia, Ottelia alismoides, Vallisneria spiralis)

Hydroleaceae - 1 (Hydrolea zeylanica)

Hypericaceae - 3 (Hypericum japonicum, Hypericum mysurense, Hypericum wightianum)

Hypoxidaceae - 4 (Curculigo orchioides, Hypoxis aurea, Molineria capitulata, Molineria trichocarpa)