Scratch just under the surface of the soil… If it is moist you should be good to go. You should regularly water Calamansi tree to keep the soil moist. Trees planted in grass should receive about 20% more water than trees with no turf or ground cover. Water use for grapefruit and lemon is about 20 percent higher than that of oranges, while water use for mandarins is about 10% less. The colour and patination of the leaves can tell you a lot about what is going on inside the plant. Dilute 2 desert spoons of the oil mix to 1 litre of water. But what about those yellowing leaves? Daily water use for an orange tree may be found in Table 1. If after 20 seconds you still don’t see water coming out of the pot, continue counting and watering for an additional 10 seconds. Spray entire tree, including both upper and lower sides of the leaves. Overwintering Citrus trees are a little tricky when it comes to overwintering, as you may already know. People often ask what you can do to prevent leaves from being shed, which often occurs in late winter - usually due to incorrect care. It’s most helpful to dig a small moat around the tree, usually eight inches from the trunk, and keep it moist. The seedlings need a very bright location. Why are the leaves of my lemon yellow? Lemon trees need to be watered every 10 to 14 days, depending on how dry the soil is. This can take up to two years. Keep the soil constantly moist. After planting, water thoroughly and place the container in a spot where your tree can receive bright sunlight. However, keeping a feel for the moisture level in the soil is one of the best ways you can gauge whether or not to water. Watering citrus trees can sometimes be tricky. When you do water your lemon tree, water it slowly and count to 20, or until you see water coming out of the pot. Make sure you know how much water your tree needs to live and grow. Larger outdoor trees will need much more, and you should refer to a professionally derived citrus care chart to get exact measurements. Deciduous trees should remain well-watered until harvest, while evergreen trees, such as citrus trees, need moist soil in fall, too. How To Water. You don’t fertilize Calamansi at this stage. It is best to water slowly and deeply to help push salt build-up past your roots. During the summer, potted and domestic lemon trees (under 6 feet in most cases) will need about 5 gallons of water per week. When you fertilize, know how many gallons of water you’ll need and mix up that much food, and then feed your plant. culate the daily water use if you know canopy diam-eter of your tree. Citrus trees tend to need regular watering when they are new. What happens in many cases is that too much water is surrounding the trees for an extended amount of time and the roots become weak. Generally this is about how far the root system extends and is where your tree is searching for the moisture and nutrients it needs. When you water your citrus trees the area on the ground that you water should be about a foot wider than the canopy of the tree. Any citrus tree needs between 6 to 8 hours of full sunlight to grow. 4. Repeat every couple of weeks as needed.