Indoor Citrus Trees

Every article and blog I've read about growing citrus trees suggests bringing them indoors for the winter if you live in the north. In my mind, I think of giving them a summer vacation outdoors. For nine months of the year, my citrus trees live inside my house. So far, this project has been only moderately successful.

Almost two years ago, I purchased three citrus trees (Dwarf Venous Orange, Dwarf Key Lime, Dwarf Meyer Lemon). The lemon tree had flowers on it, which indeed produced two lovely fruits. Since then, the trees not been able to produce any other fruit or flowers. Recently, I've learned a few things that I hope will help my citrus trees thrive. 

1. Don't over react to all the caution about watering lightly. In my case, I suspect I was under-watering for too long. Terracotta pots are best because they breathe, which reduces the possibility of over-watering. Water generously and then empty the drip trays after the excess drains. 

2. Use a special citrus fertilizer. Citrus trees tend to suffer chlorosis. The fertilizer I use is Jack's Classic Citrus FeED. 

3. Although my plants are near a window, I can hardly count on Mother Nature to provide enough light. Plant grow bulbs are plentiful---incandescent, compact florescent, LED, red and blue spectrum, and much more. Supplemental lighting is essential. My trees get about 12-16 hours of light per day. 

4. My house is cool, usually around 60 degrees or even a little less where the citrus trees are located. I suspect that my trees would like it a pinch warmer. I've recently placed them on seedling heat mats to keep their roots warm. 

5. Don't bother growing trees from seeds saved from a piece of fruit at the grocery store. They're easy to germinate and grow, but you have a 50/50 chance of growing something wildly sour and icky. 

6. Humidity is important to citrus. If you don't have a humidifier on your furnace, mist the trees frequently or build a humidity tray.

Good luck! If you have tips to share, please comment--I'd love to hear from you! 

Indoor Citrus

Mid-winter in Wisconsin can be dreary. As an urban farmer, I spend my winter perusing seed catalogs, planning next summer's veggie beds, mapping out crop rotation, and baking lots of pies and tarts with last summer's fruit harvest. 

Last winter I began indoor citrus. I purchased a bag of Meyer lemons from Trader Joe's in January 2015 and saved all the seeds from the lemons. (I also bought a bag of organic limes, only to discover they were seedless. Buyer beware!) I germinated the seeds in a small plastic bag with damp paper towels. It was easy. Then I transplanted the little seedlings into light soil and watched them take off.

To add variety to my indoor citrus grove, I purchased four trees from an online vendor---a Meyer Lemon, a Venous Orange, a Key Lime and a Mediterranean Olive tree. These trees were more mature than the seedlings I had started myself. The Meyer Lemon produced two blossoms and eventually two beautiful lemons. One of them we harvested over the weekend, which you see in the photo at the top of this blog post.

All the citrus seedlings grew rapidly over the summer. In November I transplanted them into slightly larger pots. It's been a challenging winter for my citrus trees. They have dropped nearly all their leaves and generally expressed their displeasure at my care. Nevertheless, these sturdy trees are producing tiny new shoots and leaves where the old ones fell off.

Watering citrus trees is tricky. They prefer dry soil, but not parched. It's taken me months of guessing to ascertain if I'm over- or under-watering. Finally, I purchased a moisture meter with a long probe to help me determine when to water.

This isn't an instant gratification project, but one taste of that sweet lemon juice (yes, Meyer Lemons are sweet, not sour) has motivated me to keep my citrus grove growing. It gives me hope in the winter months.