Citrus trees are trendy. The proliferation of portable trees—grafted onto dwarf rootstock—makes it possible for almost anyone to grow a lemon, lime, or kumquat without having a large space.
With the rise in popularity comes the challenge of citrus care, especially in climates with hard winters, when the subtropical trees must overwinter for months indoors in conditions that can be stressful to the plants (and sometimes to their owners). Indoor winter conditions are challenging, with lower humidity, higher and drier heat, and more difficult watering protocols.
While we feel that we have turned the winter corner and are headed toward spring, this final stretch is a crucial one for overwintered citrus, when problems that have been building up sneakily can threaten the trees we love.
Read on to learn what you might be doing wrong with your overwintered citrus, and how to fix it.
Photography by Marie Viljoen.
1. Poor drainage can kill citrus trees.
Above: The annual citrus migration in my house in Brooklyn (USDA zone 7b) begins when nighttime temperatures begin to dip reliably below 50 degrees Fahrenheit. In October my collection of two sturdy Thai limes (Citrus hystrix, also called makrut), a Meyer lemon, and a petite finger lime (Citrus australasica) is herded indoors for a long winter stay.
Citrus trees require outstanding drainage. Soggy bottoms will kill them Water must flow right through the pot and out. I mix my potting medium with large handfuls of shredded hardwood (I use a natural cedar mulch – meaning no nasty dyes). Softer woods like pine break down too fast. My mix is one-third shredded wood to two- thirds potting medium. My pots have large drainage holes in the bottom. If your pots are set in an ornamental, closed pot, it is imperative that you never allow them to stand in water. If the water stands for more than 12 hours after watering the tree, drain it (see No. 2). More work for you, but essential.
Signs of poor drainage: damp pot bottoms, constantly moist soil, fungus gnats in the room, yellow leaves, drooping leaves, leaf drop.
2. Overwatering can kill citrus trees.
Above: On average my citrus trees spend about seven months inside, going back out in late April. I have learned, sometimes the hard way, how to care for indoor citrus, so that by mid spring they are in excellent health and ready to make a break for the great outdoors.
Citrus hate having wet feet, and overwatering is the most common cause of their poor health. Do water deeply, but only water again when the pot is close to dry. Nancy Lingner, who provides customer support at LemonCitrusTree (her daughter, Crystal Kim, owns the business) recommends that you drench the pot and “drown the soil” allowing the water to run freely from the drainage holes.
To do this, Nancy likes to keep trees on a stand above a substantial plastic saucer that can accommodate one gallon of runoff. Because of space constraints I use shallow pot feet and smaller saucers. If water in the saucers touches the bottom of the pot, I let it remain in the saucer for up to 12 hours (thirsty trees will absorb this water again). But after 12 hours, I suck up excess water with a turkey baster (yes, really).
I also like to use terra cotta pots. If the outside is dark and damp at the base, this is a sign that the soil in the bottom of the pot is too wet (even if the top is dry), which is not good, so I hold off on watering. In terms of touch and feel, the top inch or two of soil will also transition from dark and moist to the touch to lighter and dry. Time to water.
Signs of overwatering: the soil stays moist every day; the bottom of a terra cotta pot looks dark, or green, and is damp to the touch; water stays standing in the saucer; the leaves are drooping, but not dry and crisp; the leaves gradually turn yellow all over and drop; little bugs like fruit flies hover everywhere – these are fungus gnats and are an indication that the pots are staying moist too long.
3. Citrus trees also hate to be too dry.
Above: Less common than overwatering, underwatering tends to happen when you go away for a few days, or simply forget. Citrus trees need deep watering, so a spritz on the surface will not help them.
Nancy reiterates that “a few cups here and a few cups there” are ineffective. Establish a schedule (I water once every seven to ten days, for example), water the citrus trees deeply till water runs from the drainage holes, and observe how fast or slowly the pots dry out.
Signs of under-watering: the soil pulls away from the sides of the pot; when you water, the water sits on top of the soil for a while before draining; water runs quickly through the pot and out; the leaves droop, and turn crisp; branches die.
Learn What Causes Leaves Falling Off A Citrus Tree
Citrus trees love warm weather and usually do quite well in warmer states. However, the warmer the weather, the more issues will be had with citrus leaf problems. You will find that in warmer climates, you will have leaves falling off a citrus tree for various reasons. Orange, lemon and lime tree leaves are all prone to the same types of problems.
Citrus Leaf Problems
The most common citrus leaf problems for lemon, lime and orange tree leaves is leaf drop. This can be caused by any number of reasons, but the most common is a great fluctuation in temperature, causing the leaves falling off a citrus tree to continue to drop until the tree can handle the temperature once more.
Citrus trees like warm weather but do best in temperatures that don’t go much above 60 to 65 degrees F. (15-18 C.) Further, whether you have your citrus trees indoors or out, you should make sure the temperature doesn’t fluctuate and is more of a constant temperature. This will definitely help stop leaves falling off a citrus tree.
Citrus leaf problems can also be caused by scale. Scale insects will cause orange, lime and lemon tree leaves to fall off the trees as well. These insects can be removed from the leaves of the citrus tree with a sharp knife. You can also use your fingernail or a cotton swab soaked in alcohol. If you find that there are too many insects to remove this way, you can spray the tree. Either spray the tree leaves with alcohol, or if you want to go a more natural route, use a mixture of lemon juice, garlic juice and cayenne pepper. Neem oil spray is effective too.
If, after checking the tree thoroughly, you find the leaves falling off a citrus tree in your home or yard, you should make sure the soil around the roots is wet enough. These trees like a lot of water and you need to water them thoroughly each time you water. Instead of just looking for signs of soil dryness, poke your finger into the soil so you can feel how damp the soil is beneath the surface.
Orange tree leaves and other citrus tree leaves are very prone to leaf drop and doing whatever you can to prevent your citrus tree leaves from dropping should definitely help your cause. If you do your best to prevent the major causes, you shouldn’t have too many problems with these hardy trees.
My Sweet Orange Tree, by José Mauro de Vasconcelos (translated by Alison Entrekin), is an autobiographical novel set in Rio de Janeiro. It introduces the reader to five year old Zeze, a precocious and mischievous child who lives much of his life in his imagination. Zeze is the second youngest of seven surviving siblings. Their father is out of work so their mother must put in long hours at a factory to keep the family afloat. There are many others living in poverty in the city but Zeze still finds their situation challenging, especially at Christmas when there is no money for fine food or presents. The hardships the family endure lead them to take out frustrations on their little troublemaker. Zeze suffers regular beatings, believing those who tell him he is a devil child and that it would be better had he never been born.
The family move house when their rent arrears become untenable. In the new back garden is a little orange tree which becomes Zeze’s friend. He plays games around it with his little brother, turning their backyard into exciting new worlds. At school he reveres his kind-hearted teacher, behaving well to please her and excelling in his lessons. Zeze earns what money he can from polishing shoes and assisting a songbook seller. He finds a friend in a wealthy adult who teaches him tenderness exists.
Zeze’s escapades are undoubtedly naughty but he is punished so regularly and severely he regards himself as unlovable. The smallest kindnesses offered are grasped and held close. Zeze may lie and swear with abandon, copying the adults around him, but he feels deeply the unfairness of the life he must accept. He shares his thoughts with his little orange tree which he believes listens and responds.
The narration is way in advance of any five year old I have come across but Zeze’s life is also unlike any situation I have known. He is cunning but never malevolent, although at times he harbours thoughts of bloody revenge when mistreated. He dreams of being a poet, finds beauty in music, is eager to learn and to be seen to attain.
Alongside the poignancy of Zeze’s day to day life there is humour, such as the inappropriate lyrics he sings because he likes the popular tune. He asks the adults he encounters whatever questions come to mind without filter, delighting in new words and their meanings. He ponders why Jesus rewards only those who already have plenty.
This is an unusual little story but one that draws the reader in. The author achieves a fine balance between conveying Zeze’s distress at his circumstances and his imaginative coping strategies. The harshness of the boy’s life is clear yet the telling never feels heavy. A story of survival and a search for love as seen through the eyes of an insightful, lonely child.
My copy of this book was provided gratis by the publisher, Pushkin Press.