How to Water Potted Lemon Trees
- 1). Add soil with a pH between 6.2 to 6.5 (you can find pH testing strips in most home improvement or gardening stores) when you first plant your lemon tree in its pot. You will only have to re-pot the tree every two to three years, depending on how quickly your tree's roots spread. Whenever you re-pot, make sure to buy a pot just one size bigger than your current one. Use a terra cotta or other type of clay pot because this porous material will allow air to reach your plant's roots as it grows.
- 2). Place your tree in a location where it will get ample sunlight. This is especially important in winter in the northern climates, when the sunlight is weak to begin with and the air is cold and harsh on your growing tree. Rotate the base of your tree every few days so that it gets equal sunlight exposure on all sides, or it may grow discolored leaves on one side, or start to lean too heavily in one direction.
- 3). Water your lemon tree with fresh rainwater, if possible. When you water, make sure the soil is thoroughly soaked through. Wait until the soil is almost dry before you water again--but make sure not to wait until it is completely dry, or you risk losing leaves and flowers from your lemon tree. If you cannot find fresh rainwater, add one-half of a teaspoon of citric acid to tap water before you water your tree. Every other week, mix a solution of one-half of a teaspoon of fertilizer into one gallon of water to get all the required nutrients to your tree.
- 4). Mist the leaves regularly to raise humidity. Lemon trees flourish best at around 50 percent humidity when they are growing. If you like, you can also set up a humidifier near the tree to keep the air moist. This is a helpful step to take in the winter, when dry air can cause your tree's leaves to turn yellow and fall out.
- 5). Keep the room temperature at or slightly above 60 degrees to help your tree absorb all of the nutrients it needs and to promote healthy growth. If possible, place your tree in a greenhouse to ensure that it gets all the warmth it requires. Use a soil thermometer to maintain the temperature of your tree's soil--you want the roots to be kept between 64 to 70 degrees in the winter, especially when you are feeding the tree with fertilizer.
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