How to Care for Citrus Trees

By February 24, 2020 February 26th, 2020 Gardening Inspiration and Advice
royal city nursery guelph citrus tree care indoor

If you’ve ever visited Southern Italy, you might have fond memories of the coastal cliffs adorned with robust lemon trees. Citrus fruits, as fruits go, are some of the most refined—from the twist of orange rind in an Old Fashioned to the fancy-lady mainstay of hot water with a slice of lemon.

As fancy and exotic as citrus fruits are, they’re not too fancy to be grown at home here in Guelph! Since citrus is fairly sensitive to cold, they do best in our region as dwarf cultivars grown in pots. With a little TLC, you can coax these elegant dwarf trees to produce gorgeous, edible fruit.

Citrus Tree Care: Not for the Faint of Heart

Citrus trees, and particularly lemon trees, are the divas of the plant world; beautiful, elegant, glamorous—and a tiny bit demanding. They need plenty of sunshine, moisture, and fertilizer to live their best lives.

This is not a project for the “get it and forget it” plant parent. These fabulous trees need plenty of attention; they need to be adored. If you’re the type who can meet their needs, they will truly become the shining stars of your home and garden. If you’re up to it, here’s what you need to know about citrus tree care in Guelph.

royal city nursery guelph citrus tree care lemon

Air and Sunlight

The first thing you need to know about citrus trees is that, while you can keep them indoors, they really want to be outside. Most citrus cultivars do best in zone 9, so in Southern Ontario, you’d be hard-pressed to find a citrus that can handle our winters. 

Your tree’s life will be one of travel—outdoors in the spring, summer, and early fall, and indoors once the frost looms. With this in mind,  keep your citrus on a rolling plant stand to easily move from one location to the next. 

If you think about the areas most famous for their citrus groves, they all have two things in common; lots of sunlight and plenty of humidity. Citrus thrives best with a minimum of 50% humidity, which is typically easy to come by in spring and summer. However, in the late fall and winter, it’s a different story. As our homes become more energy efficient and air tight, the indoor winter air becomes drier.  We can feel this effect on our skin during the winter. 

For our humidity-loving tropicals, make use of a pebble tray to keep the ambient humidity around your tree as high as possible as you get through the winter together. To make a pebble tray, use a saucer that is two to four inches wider than your pot, layer pebbles in the bottom, stand your plant on the pebbles and fill the saucer with water.  When the water evaporates, it will evaporate straight up, creating a localized microclimate with higher humidity than the rest of the room. Misting isn’t ideal, as the poor airflow indoors might increase the chances of mildew on the leaves.

Now, let’s talk about sunlight. It should come as no surprise that your citrus tree would be happiest when basking in the sun. These fruit trees prefer a minimum of eight hours of sunlight per day, and if you hope to enjoy any fruit from the tree, twelve hours is even better. Outdoors, keep your tree in the sunniest location you can find. Indoors, a powerful grow light and exposure from multiple bright windows will serve your tree well.

royal city nursery guelph citrus tree care small potted

Soil and Fertilizer

Like a diva who expects a well-appointed trailer, your citrus tree requires a properly-sized pot with high-quality soil. The soil must have excellent drainage, excellent ability to retain water, and contain a high percentage of nutrient-dense organic matter.

A high-quality potting mix with peat, perlite, and vermiculite, enriched with compost for nutrients and coir or bark chips for drainage, should suit your tree’s tastes. This blend is light and oxygen-filled, stays moist without getting too heavy, and contains a smorgasbord of food to nourish the tree’s roots.

Even with this premium potting mix, your citrus will need to be fertilized regularly. Look for a citrus-specific fertilizer at our garden centre and follow the application instructions on the packaging.

While checking the soil, keep an eye on the overall appearance of the plant. Check for signs of pests, and any dryness or discoloration of the leaves that might signal a problem. If you notice any suckers at the base, pluck them off with care. A diva must always look her best, after all.

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Watering Correctly

Citrus needs consistently moist soil, but too much water will drown the plant. The top inch of soil should be allowed to dry out before watering again, but never let it dry out all the way. How often you’ll need to break out the watering can depends a lot on the time of year, the soil you use, and several other factors. It might be easiest to simply check the soil with your finger every day. Top up the water when the soil is dry up to the first knuckle.

Again, drainage is huge. Make sure your pot has unobstructed drainage holes—standing water is bad news for your citrus tree’s roots.

Transitioning from Winter to Spring, and Back Again

When the risk of frost has passed, you can introduce your tree back to the great outdoors. However, it’s best to ease the tree back into the outdoors after having spent so many months inside. Harden off your citrus tree the same way you would harden off seeds started indoors.

At the end of the season, bring your citrus inside again. Don’t gamble with frost dates; pull your citrus indoors before the temperature dips below 10˚C, or 50˚F. 

royal city nursery guelph citrus tree care blooms

Hand-Pollinating Dwarf Citrus Trees

When you start noticing flowers on your citrus tree, make sure to pick up a clean, soft eyeshadow brush, paintbrush, or a Q tip. These are all excellent tools for hand-pollinating citrus trees, which is necessary for your tree to produce fruit. A few gentle taps on each flower will allow your tree to start forming edible lemons, limes, or oranges—and that’s a beautiful thing.

If you’re up to a little more of a challenge, your citrus tree will produce gorgeous, juicy fruit all year long. Citrus begin to fruit once they reach 3-5 years of age, but we’ve given you a few years’ head start with the specimens we carry at Royal City Nursery. Visit us today to choose one of your own—like any true diva, they have a way of stealing your heart.