adjective
luxuriant
lug-ZHOOR-ee-unt/lʌɡˈʒʊriənt/
Growing or developing in a rich, abundant way.
The fern's luxuriant fronds spill over the edge of its pot.

Etymology
Latin luxuriare meant “have to excess” or “grow profusely”; the participle describes something doing just that. Applied to vegetation, luxuriant expresses abundance through rich, thick growth.
In context
never did the fields bestow a more beautiful Harvest or the vines yield a more luxuriant vintage
More examples
- Summer rains encourage luxuriant growth in the garden.
- Her luxuriant hair falls in waves around her shoulders.
- Luxuriant vines cover the old stone wall.
Forms
luxuriant · more luxuriant · most luxuriant
luxuriantly adverb — In a richly abundant way.
luxuriance noun — The quality of rich, abundant growth.