Years ago, I first noticed Clusia used in landscaping around Miami Beach; providing a lush screening option for hotels along the boardwalk. It is heralded as low maintenance, salt and drought tolerant. Its large, succulent leaves lend a modern, tropical look to a landscape. The name Clusia actually refers to a genus of tropical plants with over 300 different species. In south Florida, the 3 most common plants in cultivation are the Clusia rosea, Clusia rosea 'Nana', and the Clusia guttifera. Contrary to popular belief, only one of these species is native to Florida. Below, I outline their main differences and potential uses in the landscape, along with important notes to consider before making the decision to plant them:
Clusia guttifera
This is the species most used as a Clusia hedge in south Florida and is often called small leaf clusia. There is a lot of misinformation about this plant being spread by the landscape industry - it is not native to Florida. It is a moderately fast-growing shrub or tree and can ultimately achieve a size of about 25 feet tall and wide. If you would like to keep it as a specimen tree instead, choose a plant that has been trained with a single, main trunk. Plants grown for use as a hedge should be full looking from the nursery.
A common landscaping mistake I've observed is to plant these too close together or too close to a wall, fence, or walkway (usually based on their small size when purchased from the nursery). I have seen plants installed as close as 1 or 2 feet apart; this gives an instantly full effect (and a happy client), but after a couple of growing seasons, the plants will become overwhelmingly large and wide (and the smiling client will be cursing the day they bought so many Clusia). The plant looks best with regular trimming as a semi-formal screen. It can be kept trimmed at a minimum of 6 feet tall and 4 feet wide - it does not perform well if it has to be severely cut back all of the time (more than 30 % of the plant is cut at one time).
Clusia rosea
This is the native plant known as pitch apple, or the autograph tree, because you can scratch your name onto the leaves, and the writing will stay as long as the leaves remain attached to the stems. If you allow it to do its thing, it can grow into a 30 foot tall tree with a 20 foot spread. You can tell it apart from Clusia guttifera because its leaves are larger (about 8 inches long) and look rippled at the tips. It has pinkish white flowers that are actually quite showy. Soon afterwards, the large, light green fruit develop and turn black when ripe. The black fruit splits open to reveal sticky, red seeds that birds will love. It is typically sold as a tree with a single leader (central trunk) and makes an excellent specimen in the landscape. Plant it in a space where it can really show off its unique trunk and prop roots.
Clusia rosea 'Nana'
This cultivar is known simply as the dwarf clusia. It has a moderate to slow growth rate and leaves about the size of a quarter. It is the best option for a planter, as a tall ground cover allowed to ramble over rocks, or as a small accent shrub. Unlike the other two Clusia, the 'nana' only grows to about 3 or 4 feet tall. This plant is a great option if privacy is not an issue, but you'd like to create a lush, green border in tough growing conditions. Performs best in full sun.
Other important things to note about Clusia:
They sprout prop and aerial roots from their lower branches like a mangrove tree. It's just what they like to do. If you don't trim it, the plant will exhibit its natural wide, sprawling growth habit.
They must be pruned by hand (in my opinion), and not cut across the leaves by an electric (or manual) hedge trimmer. Both the leaves and stems are thick; trimmers will shred them and cause gaping wounds for disease to invade. This can be time consuming and expensive if you pay someone to do your landscape maintenance.
Clusia will have a fuller shape with consistent irrigation, pruning, and full sun. Plants in the shade will exhibit a more open, sprawling shape or poor growth. This plant is not a good choice for shady situations!
There are other more sustainable alternatives...
My preference is for mixed, naturalistic screenings, where the plants are allowed to reach their mature size with minimal trimming, have a slower growth rate, or are specifically chosen based on the level of privacy screening needed. In the case where a formal hedge or border is necessary, plants with small or thinner leaves are best because they can be easily shaped with a hedge trimmer, if necessary. In my opinion, better screening options for southeast Florida include Florida privet, Florida boxwood, Ilex species, Simpson's stopper and other stoppers, crabwood, Jamaican caper, firebush, bay rum, Florida Keys blackbead, and many others.
Hope this information was helpful, and feel free to contact me to discuss alternative screening options for your space.
-Ivy