The spearmint ficus (Ficus benjamina 'Spearmint') is a variegated version of the common ficus, or weeping fig. It is a commonly used as a house plant in most regions of the U.S., except for areas where temperatures remain above freezing all year. Ficus trees cannot tolerate freezing temperatures for any length of time. They are one of the few house plants that grows into a pleasing formal tree shape when pruned correctly. They can live for many years as a house plant.
Plant a spearmint ficus tree in a container that has holes in the bottom for drainage. The ideal container leaves no more than 2 inches of potting soil between the side of the container and the root base. This is because excess potting soil collects moisture that is not used by the plant. The rotting organic matter in the excess soil creates bad odors, and becomes a breeding ground for fungus and mildew problems that can affect the health of the ficus tree.
Spearmint ficus trees do not mind being root-bound. However, if the root system is so thick that water cannot reach the entire root system when watered, then it is time to plant in a new container.
Locate the spearmint ficus tree in an area that gets as much light as possible. The tree will adapt to most light levels, but low light levels create sparse foliage. If moving from one place to another that has differing light levels, expect a 20-percent leaf drop while the tree is getting used to the new location. The plant should recover within three months. Ficus trees do not like to be moved often.
Water the spearmint ficus tree when the top inch of the soil is dry. Simply push your finger into the top of the soil to test. Ficus trees can handle more water than most house plants, but over-watering can lead to yellowing of the leaves. Occasionally, take the container to a place where you can run a large amount of water through the container to rinse out any accumulated fertilizer salts. This also drowns any pests that may be living in the potting soil. Don't forget to rinse the dust off the leaves in the process.
Fertilize your spearmint-ficus tree every two weeks with a water-soluble fertilizer suitable for houseplants. Follow directions on the container label carefully. Too much fertilizer causes burned or browning leaves and can be deadly to container plants. Before fertilizing, water the spearmint ficus tree very well. Newly formed roots sitting in dry soil can be damaged by the nitrogen in the fertilizer.
Prune the spearmint ficus tree as needed for shape. Simply shear it off at the desired level and it will bush out from there. However, frequent pruning of offending limbs is recommended rather than a drastic pruning at one time because it gives the tree time to adjust.
When the limbs are cut, a white sap, or latex, appears from the wound. It can drip on furniture or carpet, so protect these areas before pruning. Also, it can irritate the skin of some sensitive individuals. The sap should dry within a few minutes after pruning.