The way to Grow A Black Olive Tree in a Greenhouse
The olive tree (Olea europaea) is a Mediterranean evergreen fruit tree which grows outdoors in U.S. Department of Agriculture plant hardiness zones 9 through 12. Planted in the ground, the tree can grow up to 50 feet tall, but pruning will keep container-grown greenhouse olives considerably smaller. Olive trees reach fruiting age in about five years. They’re self-fruitful, but having more than 1 variety can raise yields. Fruit starts out green, turning black as it ripens.
Fill the base of a container with a well-draining potting soil. Mix in peat moss, straw or compost for extra drainage. The container must have drainage holes and be big enough to accommodate the roots of the tree, with approximately 4 inches of extra space on all sides. Upgrade the container annual if required as the tree grows. A one-gallon container will hold a 5-foot tree.
Place the tree in the middle of the container and cover the roots with the dirt. Fill the container so the dirt is approximately 2 inches from the top of the container and the crown of the tree is about an inch above the ground. Water the tree and let the soil settle, then add more soil if necessary.
Place the tree in a place that gets at least six hours of direct sunlight every day. The olive tree needs to be positioned far enough away from the windows so the sun doesn’t burn the leaves.
Water the olive tree with a minimum of 1 inch of water per week. Feel the top of the dirt. When the top inch is dry, the tree needs to be watered.
Fertilize with a balanced fertilizer monthly through the winter months, and every 2 weeks during active summer growth. Utilize a slow-release fertilizer to fertilize less frequently. Add a hydrogen peroxide once annually about a month prior to the plant must begin to bloom. Follow the manufacturer’s directions on the fertilizer label.
Maintain the greenhouse temperature above 50 degrees Fahrenheit, with higher daytime temperatures than nighttime temperatures when possible. For the olive oil to blossom and fruit, then it needs 2 months of cold chilling at 46 to 48 degrees Fahrenheit during the winter months.
Prune out dead or damaged branches when you see them. Cut the division back to just outside the branch collar with pruning shears or a pruning saw. To control height and keep the shape, prune branches back to the desired span each spring. Utilize the cut 1/4-inch out a leaf node, bud or lateral branch.
Pinch the tips of shoots to support branching as soon as the tree grows to 5 feet tall.