How to Grow Fatsia japonica Indoors

Combine 3 parts potting soil, 2 parts acidic compost, and 1 part perlite to create a soil mix suited to growing Fatsia japonica plants indoors. Mix the components until the perlite is evenly distributed.

Fill a large ceramic planter with the soil mix. Firm the surface to create a 1-inch gap between the surface of the soil and the lip of the pot. Pour water over the soil until moisture trickles out the bottom of the pot.

Dig a planting hole with the same dimensions as the Fatsia japonica's original pot. Remove the plant from its pot, and press the root ball into the hole. Firm the soil around the roots.

Position the Fatsia japonica near a large window with southern, western or eastern exposure. Measure the light at the desired location using a light level meter to ensure it is above 250 foot-candles.

Maintain temperatures above 55 degrees Fahrenheit at night and 68 to 75 F during the day. Place a screen or other barrier between the plant and any nearby doors to protect it from cold drafts during the winter months.

Water the Fatsia japonica plant whenever the top inch of soil feels dry. Add water until the soil feels moist at a depth of 3 inches. Decrease water during the winter to 3 inches whenever the top 2 inches feel dry.

Feed the Fatsia japonica plant with a balanced 10-10-10 ratio fertilizer once a month from March until September. Apply the fertilizer as directed on the label, and water thoroughly afterward.

Prune off older branches with diminished vigor in late winter around mid February. Snip the branch at its point of origin without disturbing the younger growth emerging at its base. Use pruning shears or a sharp budding knife to prune Fatsia japonica.

Top-dress the soil each spring with acidic compost. Spread a 1- to 2-inch layer of compost around the base of the plant. Water the plant thoroughly afterward to wash the acidity into the soil.

Repot Fatsia japonica plants every two to three years to encourage growth. Choose a ceramic or molded plastic planter with a 1- to 2-inch increase in size. Use a fresh batch of the soil mixture created in Step 1 for repotting.