Coffee (Coffee arabica) is a shrubby evergreen plant that produces fragrant white flowers in early spring, followed by small oblong fruits called “cherries.” The cherries can take up to nine months to ripen to a red-purple color and often contain two coffee beans inside them. The beans are harvested to either produce more coffee plants or to roast, for making into the popular beverage “coffee.” Hardy to U.S. Department of Agriculture hardiness zones 10B through 11; coffee plants have a rounded growth habit, reaching 8 to 15 feet tall at maturity. They can be cultivated indoors under artificial lighting or grown outdoors in sub-tropical regions.
1. Place 20 freshly harvested, unroasted coffee beans in a shallow dish and fill with about 1 inch of lukewarm water. Soak the beans for 24 hours before removing them from the dish. Discard any bean that does not have a tiny white bump emerging from its end. There should be about five to eight viable coffee beans remaining.
2. Fill a 6-by-6-inch container to the brim with vermiculite. Plant one viable coffee bean 1/2-inch deep in the center of the container. Cover the top of the bean loosely with vermiculite. Repeat the process for each viable seed.
3. Set the containers in an interior room that receives at least six hours bright, indirect sunlight per day. Air temperatures in the room should be about 75 degrees Fahrenheit throughout the day and night.
4. Water each starter container thoroughly until the vermiculite is moist to a 6-inch depth, using a spray bottle set on a fine mist. Mist at planting and at least once a day thereafter. Do not let the vermiculite dry out between waterings.
5. Cover the top of the starter containers with a layer of plastic wrap, securing it tightly around the edges. Leave the plastic wrap on the containers throughout the germination process, lifting it only for daily watering. The plastic wrap can be removed completely at the first signs of germination. It can take up to 60 days for the coffee bean to germinate.
6. Transplant the coffee plants once they reached at least 6 inches tall. Transplant into the center of a 5-gallon container filled with potting soil or directly into the ground in subtropical areas only. Dig a hole that is 7 inches wide and just as deep as the root ball of the coffee plant. Remove the plant from its original container and set upright in the center of the hole. Back-fill around the root ball with soil, ensuring that the roots are completely covered. In subtropical areas, the planting location should be in a have well-draining soil and receive at least six hours of indirect sunlight each day. Repeat this process for each desired coffee seedling.
7. Water the coffee plants to a depth of 6 inches at planting time and every day thereafter, using a watering an. Allow the soil to dry out slightly between watering.
8. Set the coffee plants that were transplanted into 5-gallon containers indoors underneath fluorescent grow lighting. Leave a 12-inch space between the top of the coffee plants and the artificial lighting. Set a light timer so that the artificial lighting stays on for 12 hour per day, turning the lights off and on at the same time each day. Move the light higher as the plant grows, always leaving 12 inches between the coffee plants and the lighting. Mist the coffee plants with a spray bottle daily until the all the leaves are saturated.
9. Place an even 1-inch layer of organic fertilizer around the base of the coffee plants in the springtime. Start 2 inches from the plant, stopping at the edge of the container or outer edge of the drip line for coffee plants that are planted outdoors in the ground.