Yes, you can grow blood orange tree indoors with the right setup at home. You need a dwarf cultivar, a large pot, strong grow lights, and cool nights. Plan to give your tree daily care and a summer trip outside each year to keep it healthy.
I keep a dwarf Moro tree by my south facing window through the winter months. The tree gets 12 hours of daily light from a full spectrum LED bulb mounted above the pot. It set 8 small fruits last winter and ripened them by March without any trouble at all.
Indoor citrus growing has one big hurdle to clear from the start. The air inside your home gives only 10% to 25% of the light strength your tree would get outside. Without extra light from a grow lamp, the tree drops leaves and slows down its growth.
Room temperature poses the second hurdle for an indoor blood orange tree. Warm nights above 65°F (18°C) stop the anthocyanin from forming. Your fruit will turn out pale orange instead of the deep ruby color you want. Aim for night temps near 55°F (13°C) in a cool room or basement.
Pick a dwarf grafted tree on a small rootstock like Flying Dragon for the best fit indoors. The dwarf rootstock keeps the tree under 6 feet (1.8 meters) tall. You will have an easier time moving it between rooms and out to the patio each summer with this size.
Plant your tree in a 15 gallon (57 liter) fabric smart pot for good drainage and root air. Fill it with a fast draining citrus mix that holds some moisture but never stays soggy. Soggy roots are the top killer of indoor citrus by a wide margin.
South-facing window citrus placement gives your tree the most natural light of any spot in the house. Push the pot right up to the glass for full sun exposure. Rotate the pot a quarter turn every week so all sides grow evenly toward the light source.
Indoor air gets dry from heating systems all winter long, and citrus hates dry air. Run a humidifier near your tree to keep humidity at 40% to 60%. Mist the leaves twice a week if you cannot run a humidifier all the time.
Add a 100 to 200 watt LED grow light above the canopy to fill the gap when the sun is weak. Set the light on a timer for 12 hours each day. Hang it about 12 inches (30 cm) above the top of the tree for the best coverage.
I tried to skip the grow light my first winter and watched my tree drop half its leaves by January. Adding a cheap $60 LED grow light fixed the problem within four weeks. The tree pushed new growth and held its leaves through the rest of the cold season.
Water your container blood orange only when the top inch of soil feels dry to the touch. A pot that small dries out fast in heated rooms, so check the soil every two days. Feed monthly with a balanced citrus fertilizer during the spring and summer growth flush.
Move your tree outdoors in late spring once nights stay above 50°F (10°C) for good. The full strength of outdoor sun will push fast new growth and stronger branches. Place the pot in part shade for the first week to prevent leaf burn from the bright sun.
Bring the tree back inside in fall before the first frost hits your area for safety. Check the leaves and pot for pests before you carry it through the door. A quick spray with insecticidal soap stops aphids and scale before they spread to your other house plants.
An LED grow light citrus setup costs about $80 to $150 to start from scratch. The light pays for itself over a few years by keeping your tree alive and fruiting each winter. Your reward is fresh ruby fleshed oranges from your own home no matter where you live.
Read the full article: Blood Orange Tree Complete Guide
