How to Grow an Olive Tree Indoors: 4 Care Tips for Olive Trees

An olive tree is an evergreen tree native to the Mediterranean region of Europe and Africa, and parts of Asia. Olive trees typically grow no taller than 30 feet, though varieties that grow in a container may only reach a fifth of that size. For example, the non-fruiting dwarf olive tree, which is best for indoor planting, reaches around six feet in height when mature.

Both the tree and its fruit—a small stone fruit that, when ripe, turns green or purple—are referred to as “olive,” while its botanical name is Olea europaea, or “European olive.” Both olives and olive oil, the liquid fat produced by pressed olives, are nutritious and have been staples of a Mediterranean diet for thousands of years.

The best time to plant an indoor olive tree is during the early spring and summer months. Olive trees need full sun and six to eight hours of bright, direct sunlight to survive. Positioning the olive tree in front of an east- or south-facing window in a dry, spacious room, like the living room, is an ideal spot.

Olive trees thrive in climates with hot, dry summers and cool, moist winters inherent to Zone 8 on the USDA Plant Hardiness Zone Map, which includes much of the Pacific Northwest and American South. The trees are less likely to survive in temperatures below 15 degrees Fahrenheit.

The easiest way to grow an olive tree is from a cutting or purchasing a young dwarf variety from your local garden center or nursery. Here’s a step-by-guide to growing an olive tree indoors:

1. 1. Choose a suitable variety for your space. There are many different varieties of olive trees, but certain types make better indoor plants than others. The non-fruiting dwarf variety is the best choice for indoors: the Arbequina olive tree, from the Catalonia region of Spain, is a good choice for small spaces since it doesn’t reach more than a few feet when mature. While the Arbequina is self-fruiting, it is unlikely to produce fruit when growing indoors because there is usually not enough sunlight to encourage the process.
2. 2. Pick the soil. Indoor olive trees grow best in large containers with drainage holes. Choose a free-draining potting mix, like sandy cactus potting soil, for your olive tree. Options with lightweight additions like perlite or gravel can help with draining.
3. 3. Plant in a new container. If your tree is in a nursery container, you may want to plant it in a larger pot, so that you don’t have to repot it so quickly down the line. Remove the tree from the container and take note of how deeply it was planted. Gently separate the roots in the root ball. Plant the tree in the new container and add enough soil, so you can bury it at the same depth as it was in the nursery container.
4. 4. Propagate. To grow an olive tree from a cutting, you’ll need an eight- to nine-inch stem with a leaf node or two from a tree that has already fruited. Next, fill your pot with sandy cactus potting soil, then place the cut-side of the branch about halfway down into the soil. Pack the soil around the cutting, covering the top of it. The roots can take a few months to establish, so you’ll need to water the plant every day to encourage germination.
   
5. 5. Water. Water your tree thoroughly each week during its first year, and let the excess water drain through the bottom of the pot into a second container. Add more water when the top two inches of potting soil feel dry to the touch, but note that olive trees grow more slowly during the fall and winter months. When the tree seems to be thriving in its pot, you can reduce watering to once a month.
6. 6. Fertilize. Use a nitrogen-based houseplant fertilizer once a month during fall and winter before switching to a slow-release fertilizer twice a month in the early spring. Composts and mulches are not necessary since they hold more moisture than the olive tree needs.

Here are some tips that can help you grow a healthy olive tree indoors:

1. 1. Keep the leaves away from the window. Keep the tree’s leaves away from the surface of the window, which becomes warm from sunlight and can burn them. If the plant is not getting enough direct light, its greenery begins to drop off during the winter months, so you may need to provide more light through artificial means for the tree to thrive.
2. 2. Prune. Prune your olive tree to retain a preferred height or shape—indoor olive trees work well as bonsai—or if it looks like it’ll outgrow its pot. Wait until the autumn of the tree’s second year to prune.
3. 3. Monitor for pests. Both indoor and outdoor olive trees are susceptible to damage from insect pests. Chief among these is the scale, a hard-shelled insect that can break through the tree’s leaves and trunk with its hard mouthpieces to drain the sap. Routinely check the underside of the tree’s leaves, and use insecticidal soap to repel the invaders. Spittlebugs, too, can be a hassle for olive trees because they carry bacteria that can be potentially fatal to these plants.
4. 4. Repot as necessary. The olive tree’s roots will become crowded inside your container after its first year, so you’ll need to repot within its first few years of life. Only move the tree up one pot size at a time, and if it’s already in the biggest container you can or want to use, add a few inches of new potting soil.

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