Common names: L
- lablab bean
- lace cup viburnum
- lacebark pine
- lacecap hydrangea
- lacy autumn fern
- lacy phacelia
- lady fern
- lady finger cactus
- lady's bedstraw
- lady's leek
- lady's mantle
- lady's slipper orchid
- lady's smock
- ladybird poppy
- lamb's ears
- lamb's tail
- lance-leaf tickseed
- land cress
- lantern hibiscus
- larch
- large bittercress
- large blue alkanet
- large camas
- large dendrochilum
- large flowered trillium
- large flowering mullein
- large fothergilla
- large hop trefoil
- large masterwort
- large Mediterranean spurge
- large self-heal
- large speedwell
- large stinging nettle
- large yellow foxglove
- large-flowered bellwort
- large-flowered blanket flower
- large-flowered evening primrose
- large-flowered mountain trumpet
- large-flowered rhododendron hybrid
- large-flowered tickseed
- large-leaved bamboo
- large-leaved lime
- largeflower fleabane
- larger bindweed
- larkspur
- Latin American fleabane
- laurel
- laurel-leaved rock rose
- laurestine
- laurustinus
- Lavalle hawthorn
- lavandin
- lavender
- lavender cotton
- lavender mist meadow rue
- lawn daisy
- Lawson's cypress
- leadplant
- leadtree
- leadwort
- leaf cactus
- leaf celery
- leaf mustard
- leafcup
- leafless dendrobium
- leafless spurge
- leafy goosefoot
- leafy leopardsbane
- leafybract aster
- leather flower
- leatherleaf mahonia
- leatherleaf viburnum
- Lebanese fritillary
- Lebanon cedar
- Lebombo cycad
- lemon
- lemon balm
- lemon bee balm
- lemon eucalyptus
- lemon lavender
- lemon scented ironwood
- lemon scented myrtle
- lemon scented pelargonium
- lemon verbena
- lemon-scented gum
- lemon-scented tea tree
- Lenne's magnolia
- lenten rose
- leopard flower
- leopard plant
- leopard's bane
- lesser bottlebrush
- lesser burdock
- lesser butterfly orchid
- lesser calamint
- lesser celandine
- lesser duckweed
- lesser honeywort
- lesser periwinkle
- lesser snakeroot
- lesser Solomon's seal
- lettuce
- Lewis flax
- Leyland cypress
- Liberian coffee
- licorice
- lilac
- lilac hibiscus
- lilac penstemon
- lilly pilly
- lily
- lily leek
- lily magnolia
- lily of the Nile
- lily of the valley
- lily of the valley shrub
- lily turf
- lily-flowered tulip
- lilyturf
- limber pine
- lime
- Lincolnshire spinach
- linden
- Lindley's blazing star
- lingonberry
- linseed
- lion's ear
- lion's tail
- liquorice
- little evening primrose
- liverleaf
- liverwort
- living stones
- lizard orchid
- lizard's tail
- lobelia
- loblolly pine
- locust
- lodgepole pine
- lollipop plant
- London pride
- long beech fern
- long-leaved lungwort
- long-leaved speedwell
- long-leaved whorl flower
- longleaf speedwell
- loose-leaf lettuce
- loosestrife
- lopsided star orchid
- loquat
- lotus
- lotus flower
- lotus vine
- Louisiana phlox
- lovage
- love in a puff
- love lies bleeding
- love-in-a-mist
- Low's cymbidium
- Lucile's glory of the snow
- lucky clover
- lucky plant
- Lucombe oak
- lulo
- lungwort
- lupin
- lupine
- lychee
- lydia broom
- lyme grass