I recently bought a Meyer Lemon tree. It’s about 2 or 3 feet tall. I have it directly under a grow light and covered with plastic wrap because the room that it is in is chilly. I’m not sure why but the leaves are curling up. I have checked online and it says that it needs less water (although I was only watering about once a week). Then another site said I should water more, so I watered deeply. It’s getting worse and I don’t know what to do. I have already lost a really nice lemon bush with about 40 lemon buds on it about a year ago (they all fell off and the bush died). Please help. Thank you.
Sorry to hear you are having a challenge with your Lemon Tree (Citrus x limon ‘Meyer’) and thank you for submitting the photo. These plants are attractive while in fruit or flower and there is ever the promise that plants will bear fruit again but you could well have a long wait.
It is best to know a little about these plants natural habitat and try to replicate these conditions to increase your chance of success. Citrus is a sub tropical genus. For optimum growth they require temperatures of 58-86F (15-30 C) although most species will survive for short periods at 32F (0 C). They thrive at altitudes of 320 ft (100m) or above with humidity levels of 60-70 percent. These plants tolerate a wide variety of soils but do best in fertile, well-drained, slightly acidic soils (pH 6-6.5). So for home growing you need to provide good drainage, careful watering, ample feeding, full sun (a summer spent outdoors) and cooler conditions in winter.
Looking ahead to next year plan to put this plant out of doors during the summer months (pick a sheltered site). As a result of being exposed to the sun and the elements it may oblige by flowering and fruiting again.
Bring your lemon tree indoors before the weather gets too cold and keep it in an environment that meets its light and temperature needs. Make sure the temperature is not subject to fluctuation such as draughts. Careful watering means avoiding erring on the wet side so allow the surface to become dry between waterings. Feed with a tomato fertilizer once a month while your plant is actively growing. Help the air humidity by misting occasionally, especially when flower buds are opening. If you need to repot do this in the spring and you could try to take stem cuttings in the spring as well (as an insurance policy) or try planting a lemon pip in the spring.
From the photo you provided and your mention of the demise of your previous plant, there could be a wide range of factors causing the leaves to curl and fall. Factors including too little heat, or over watering or cold draughts. You may also wish to look at the University of California’s Master Gardeners of Orange County website which has a section on citrus trees.
Here you will find additional information and further clues as to what could be causing the leaf curl. An extract from this information is as follows:
If the leaves on your citrus are curling, there are three common possibilities:
1. Some insect pests will cause some leaf curl. In spring, aphids might do this on soft new leaves. Look inside the curl for presence of insects. If none are present, consider 2 or 3 below.
2. Overwatering can cause leaves to curl or cup INWARD. Also, stress from very hot weather will cause leaf cupping
3. Sometimes leaves will cup DOWNWARD in the late fall or early winter. This is not a problem to worry about, as the new growth will come out with normal shaped leaves in the spring.
There are also a number of pests and diseases that could cause leaf curl. Keep a careful eye on your plant for signs of trouble and make any necessary adjustments to its environment/care and good luck!