Indoor Tree for Condo Environment

(Question)

Hi there,

I am thinking either purchasing an indoor orange tree or an indoor olive tree. What species of either plants would you recommend? I prefer a species that is low maintenance. I also want to understand the full scope of taking care of either of these trees prior to purchasing as this will impact my decision. I understand sunlight, temperature and appropriate watering schedules are important but is there anything I should be aware of before owning one of these trees? Lastly, is there a place that you would recommend for the purchase within the city of Toronto or GTA?

My current situation: living in a condo with constant sunlight throughout the day and even more sunlight in the afternoon (west facing windows). 10ft ceilings and HVAC vents are next to the window.

(Answer)

Thank you for sending your question to the Toronto Master Gardeners. It sounds like you have a wonderful setup for an indoor tree, I hope that my suggestions will help you in making your decision.

Orange trees would be the “prima donna” of your two options.

Orange trees belong to the family Citrus rutaceae, that are   comprised  of approximately 15 species of small trees ad shrubs including lemons, limes, oranges, and tangerines.  They can make extremely attractive house plants because of their glossy green leaves, and dainty flowers and occasionally – in perfect conditions – can bear fruit.  Yes, they are certainly attractive, but low maintenance they are not.  If you are up for the challenge here are the requirements to note;

It sounds as if you have adequate light as these plants will need between 4 to 6 hours of sun daily, but Citrus trees do not do well with central heating.  They need high levels of humidity but too much water will surely kill your plant.  They need temperatures of between 16 – 21 C, high temperatures and in addition,  drafts (either hot or cold) will cause stress to your plant.  .  Make sure that you use a slightly acidic container soil and your container must have good drainage.  During the winter months you will need to increase humidity by using a humidifier, spritzing, or placing planter on trays of damp pebbles or peat moss.  As with most house plants water moderately, allowing the top to dry before watering and definitely not allowing soil to feel soggy.  During the growing period (spring and summer) feed with a diluted, high potash, tomato type fertilizer.  Do not feed during the winter (or dormant) season.

Recommended Citruses:

C.limona (otaheite orange) is a hybrid between a lemon and mandarin.  It has no thorns  and grows in a bush like shape, producing deep yellow to orange fruit up to 2” in diameter.

C.mitis (calamondin orange) is the most popular indoor citrus.  It grows up to 4’ and can produce fruit while still very small.  In perfect conditions it produces profusely, so much so that you will have to thin the fruit so as not the weigh down the branches.

I have included a link to the University of Minnesota’s guide to growing indoor citrus.

Citruses are susceptible to pests such as Scale, mealybugs, whitefly, and spider mites.  I have included a link to our gardening guide on controlling pests with pesticides.

Much less fussy is an Olive tree.  It too is very attractive with narrow silvery sage leaves.  Even the dwarf varieties can grow to over 6 feet, so pruning will be necessary as well as increasing the container size every few years.  Many of its requirements are similar to that of the Citrus; They are sun loving and Olive trees (Olea europaea) need to be grown in containers with excellent drainage.  You should use a mixture of potting soil combined with sand (or cactus soil) to ensure that all-important drainage.  Unlike Citrus trees, olives can do without the high humidity, but do keep them away from drafts.  Your olive tree will benefit from a balanced houseplant fertilizer (20-20-20).  Apply once per month during winter, bi-monthly spring, and summer.

Unfortunately your olive tree will not produce fruit unless you mimic winter conditions (temperatures below 10C) for two months.  Also, although relatively low care, they typically only live for 8 to 9 years.

They do attract some pests, so do check the link below for some guidelines.

The two most common varieties grown as indoor plants are:

O.Arbequina.  Spanish variety, with silvery leaves.  It can grow up to 8 feet.  O. Picholine.  French variety, with pale green leaves.  This variety can grow up to 10 feet

As to where to find these plants, try your local nursery; we are not permitted to provide specific recommendations on where to purchase plants. Ontario’s Ministry of Agriculture, Food & Rural Affairs has a website entitled Fruit Tree Nurseries in Ontario which provides the names & contact information for several nurseries. These mainly relate to trees to be grown outdoors,, but these experts may be able to help you source an olive or citrus tree to grow in your home

I do hope you have found this helpful, good luck with growing your indoor tree.