Alternative title:  How to Have an Orangerie Even if You Aren’t a Member of a Royal Family

Alternative Title #2 : Juicy Fruits – The Taste is Gonna Move Ya

Few indoor plants can combine so much value within a single pot as citrus trees. There are the obvious benefits – a lovely, small tree, often bedecked with colorful fruit which, to be honest, is so pretty that one feels a little guilty picking even a single orb that took half a year to ripen. But don’t be too enthralled with the citrus tree’s beauty, you will be denying yourself one of the greatest pleasures for the palate and soul because freshly picked citrus tastes nothing like the supermarket fruit. If you don’t believe me, just scratch the rind of any containerized citrus while it is still on the tree, and inhale the oil. The smell begins evaporating just hours after the fruit is picked, leaving most people with a completely different citrus experience.

I learned this once while visiting a farm in California. The proprietor took me over to an old, gnarly kumquat tree with its branches hanging heavy with brilliant orange fruit. “Go on, eat it but eat it whole,” he said.

“Eat it whole?” I thought. “Yuck, but…OK.”

Do you know that scene in the animated Disney film “Ratatouille” when the rat first experienced French cuisine? Yeah. It was kind of like that. I swear that I saw colored, swirling lights in my eyes. My mouth exploded first, and then my mind.

The sugars and oils in the skin of freshly-picked produce make all the difference in the world when it comes to their flavor profile. Kumquats are like the flavor of tangerine Life Savers with the flavor scent of orange blossoms, lemon blossoms and cotton candy. Really – heaven tastes like this. Perfume-y, tangy, sour and sweet. Boom.

Needless to say, I was very disappointed when I returned home to snowy New England and I picked up a pack of kumquats at the store. I popped one in my mouth and the taste was bitter and dry. I knew then that I just had to grow some myself.

In my first winter of raising a few small trees indoors and in the greenhouse, I discovered that by the middle of January, I had so much fruit, that I could not use it all.

Before you start, however, there are a few things you must know. First off – those little sprouted seeds that you found in the grapefruit this morning? Throw them away.

Forget any visions of raising your own clementines from a paper towel full of seeds. It’s just not going to happen for many botanical and agricultural reasons. If you want to try raising your own from seed, you may have the best luck with Key limes, but even with those, expect at least an 8-10 year lead time.

You will have practically a foolproof harvest if you buy your plants, either from your local nursery, or from a mail order source. Like many fruit trees, citrus are generally enhanced by grafting, especially with named cultivars. If you want to raise a mandarin orange (clementines to most of us) then buy an established grafted plant. The larger it is, the sooner you will have fruit. The benefits of grafted trees go far beyond the citrus farm, particularly with indoor culture, varieties are grafted to enhance early blooming and fruiting, and, most importantly, a smaller, more reasonably sized tree.

Finding the perfect citrus plant is not always as easy as one expects it to be. Citrus plants are highly regulated due to a long list of agricultural diseases which can be spread from one farm to the next. There is a reason why the Department of Agriculture has a check off box on your flight back from Hawaii. Citrus farming is big business. Don’t let this stop you however; regional sources can be found, or mail order sources which can sell inspected plants ready for you to place into a pot.

Good varieties of citrus are rarely inexpensive as the grafting process adds at least an additional year onto the growing cycle on the nursery side, but it you are going to bother with trying to raise your own fruit, the initial investment won’t be regrettable, especially after five years when you have a strong, healthy tree full of fruit while the snow flies outside. Plan on spending $30 or more for a proven indoor variety, one which has been carefully grafted.

In many ways, keeping citrus indoors is akin to keeping chickens. Invest in good stock, care for them well with food and water, fresh air in the summer and bright sunshine, and in mid winter, you start reaping the rewards. My two ‘Improved Meyer’ lemon trees provide my kitchen with nearly 150 lemons each winter. That supplies us with at least 2 lemons a day for drinks and tea, plus a few dozen left over for marmalade.

Although I keep my plants in a cool greenhouse in Massachusetts, before I built it the citrus were raised in two spare bedrooms which were kept cooler than the rest of the house. Really, all that is needed is a sunny window, and a room with a temperature shift from day to night, which will help keep the trees fresh and vibrant. Most citrus prefer indoor conditions, as long as your home isn’t too hot and dry. The easiest ones to grow are Kumquats, citrons, lemons and limes can be abundant enough that you would not have to buy any fruit for an entire winter.

Aside from the somewhat practical reasons of actually having fruit in abundance, don’t dismiss the holistic reward of fragrance. I mean, lemon blossoms? Really.

Speaking of flowers, good pollination is not always a sure thing when your plants do bloom, so set any blooming plants outdoors on a mild day to allow bees to do their job, or just hand pollinate with a soft watercolor brush. Small fruit will begin to form after the blossoms shatter, and should slowly grow throughout the summer. One of the best things one can do for a home grown citrus tree, however, is to set it outdoors for the summer. The benefits are many, but mostly, it gives you a vacation from watering it, and it will help the plant thrive.

Citrus raised in containers prefer a soil which is rather low in organic material. While an on-line search will uncover dozens of recommended soil mixes containing wood bark and commercial potting soil, I fear that many writers are simply repeating found cultural information which often isn’t accurate. Commercial growers know that citrus prefers a sandy or loamy soil, but container-raised plants will need additional drainage material, as nothing will kill a citrus as quickly as soggy roots.

Citrus also prefer to be under-potted, meaning that they prefer smaller pots rather than larger pots. The good news is that a citrus tree can remain in the same pot for 10 years or more, once they are large enough for a 12 or 14 inch pot. Weight can be a problem, but you are more likely to succeed if you use a clay pot, which is more forgiving when it comes to moisture retention.

Nutrition is perhaps the most perplexing skill to master. Basic multi-purpose formulas will only go so far, but all plants appreciate a higher dose of nitrogen when they are young, preferably in the spring and summer. Yellow leaves, are the most common problem which can seem problematic to home growers. One of the fastest way to kill a citrus tree is to over fertilize in an effort to remedy yellowing leaves. Iron deficiency is the most common diagnosis, and it is easy to remedy with a citrus fertilizer containing chelated zinc or iron. Your basic big box store may not carry such a blend, but it can almost always be found at a hydroponic supply store.

Lastly, don’t be afraid to prune your trees, taking care to not trim below any grafted parts. Citrus can handle rather harsh pruning, but don’t get crazy and try to create a topiary or a perfect form, citrus grow in spurts of only once or twice a year, so keep your most severe pruning to late winter before flowers form.

By Matt Mattus

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