Your Elaeocarpus japonicus will not be too picky about how you choose to water it. As such, you can use just about any common watering tool to moisten this plant’s soil. Watering cans, hoses, and even cups will work just fine when it is time to water your Elaeocarpus japonicus. Regardless of which watering tool you use, you should typically apply the water directly to the soil. In doing so, you should ensure that you moisten all soil areas equally to give all parts of the root system the water it needs. It can help to use filtered water, as tap water can contain particles that are harmful to plants. It is also beneficial to use water that is at or slightly above room temperature, as colder or hotter water can be somewhat shocking to the Elaeocarpus japonicus. However, the Elaeocarpus japonicus usually responds well to any kind of water you give it.

For outdoor plants, especially newly planted plants or plant seedlings, they can be prone to lack of watering. Remember that you need to keep watering enough for a few months when the tree is small or just planted. This is because once the roots are established, Elaeocarpus japonicus can rely on rain most of the time. When your Elaeocarpus japonicus is planted in pots, overwatering is often more likely to.When you accidentally overwater your Elaeocarpus japonicus, you should be prepared to remedy the situation immediately. First, you should stop watering your plant right away to minimize the effect of your overwatering. After, you should consider removing your Elaeocarpus japonicus from its pot to inspect its roots. If you find that none of the roots have developed root rot, it may be permissible to return your plant to its container. If you do discover signs of root rot, then you should trim away any roots that have been affected. You may also want to apply a fungicide to prevent further damage. Lastly, you should repot your Elaeocarpus japonicus in soil that is well-draining. In the case of an underwatered Elaeocarpus japonicus, simply water this plant more frequently. Underwatering is often an easy fix. If you underwater, the plant's leaves will tend to droop and dry out and fall off, and the leaves will quickly return to fullness after sufficient watering. Please correct your watering frequency as soon as underwatering occurs.

Most plants that grow naturally outdoors can be allowed to grow normally with rainfall. If your area lacks rainfall, consider giving your plants adequate watering every 2 weeks during the spring and fall. More frequent watering is needed in summer. In winter, when growth becomes slower and plants need less water, water more sparingly. Throughout the winter, you may not give it additional watering at all. If your Elaeocarpus japonicus is young or newly planted, then you should water more frequently to help it establish, and mature and grow up to have more adaptable and drought tolerant plants. For potted plants, there are two main ways that you can determine how often to water your Elaeocarpus japonicus. The first way is to set a predetermined watering schedule. If you choose this route, you should plan to water this plant about once every week or once every other week. However, this approach may not always work as it does not consider the unique conditions of the growing environment for your Elaeocarpus japonicus . Your watering frequency can also change depending on the season. For instance, a predetermined watering schedule will likely not suffice during summer when this plant's water needs are highest. An alternative route is to set your watering frequency based on soil moisture. Typically, it is best to wait until the first two to four inches of soil, usually ⅓ to ½ depth of the pots, have dried out entirely before you give more water.

When it comes time to water your Elaeocarpus japonicus, you may be surprised to find that this plant does not always need a high volume of water. Instead, if only a few inches of soil have dried since your last watering, you can support healthy growth in the Elaeocarpus japonicus by giving it about five to ten ounces of water every time you water. You can also decide your water volume based on soil moisture. As mentioned above, you should note how many inches of soil have dried out between waterings. A surefire way to make sure your Elaeocarpus japonicus gets the moisture it needs is to supply enough water to moisten all the soil layers that became dry since the last time you watered. If more than half of the soil has become dry, you should consider giving more water than usual. In those cases, continue adding water until you see excess water draining from your pot’s drainage holes. If your Elaeocarpus japonicus is planted in an area that gets plenty of rain outdoors, it may not need additional watering. When the Elaeocarpus japonicus is young or just getting established, make sure it gets 1-2 inches of rain per week. As it continues to grow and establish, it can survive entirely on rainwater and only when the weather is hot and there is no rainfall at all for 2-3 weeks, then consider giving your Elaeocarpus japonicus a full watering to prevent them from suffering stress.

Overwatering is a far more common problem for the Elaeocarpus japonicus, and there are several signs you should look for when this occurs. Generally, an overwatered Elaeocarpus japonicus will have yellowing leaves and may even drop some leaves. Also, overwatering can cause the overall structure of your plant to shrivel and may also promote root rot. On the other hand, an underwatered Elaeocarpus japonicus will also begin to wilt. It may also display leaves that are brown or brittle to the touch. Whether you see signs of overwatering or underwatering, you should be prepared to intervene and restore the health of your Elaeocarpus japonicus.

When the Elaeocarpus japonicus is very young, such as when it is in a seedling stage, you will need to give it more water than you would if it were at a mature age. During the early stages of this plant’s life, it is important to keep the soil consistently moist to encourage root development. The same is true for any Elaeocarpus japonicus that you have transplanted to a new growing location. Also, the Elaeocarpus japonicus can develop showy flowers and fruits when you give them the correct care. If your Elaeocarpus japonicus is in a flowering or fruiting phase, you will likely need to give a bit more water than you usually would to support these plant structures.

The seasonal changes will affect how often you water your Elaeocarpus japonicus. Mainly, during the hottest summer months, you will likely need to increase how much you water this plant, especially if it grows in an area that receives ample sunlight. Strong summer sunlight can cause soil to dry out much faster than usual, meaning that you’ll need to water more frequently. By contrast, your Elaeocarpus japonicus will need much less water during the winter, as it will not be in an active growing phase. During winter, you can get by with watering once every 2 to 3 weeks or sometimes not at all. For those growing this plant indoors, you should be somewhat wary of appliances such as air conditioners, which can cause your plant to dry out more quickly, which also calls for more frequent watering.

In some cases, your Elaeocarpus japonicus may not need any supplemental watering when it grows outside and will survive on rainwater alone. However, if you live in an area of little to no rain, you should water this plant about every two weeks. If you belong to the group of people who live out of this plant's natural hardiness zone, you should grow it indoors. In an indoor setting, you should monitor your plant's soil as it can dry out more quickly when it is in a container or when it is exposed to HVAC units such as air conditioners. Those drying factors will lead you to water this plant a bit more often than if you grew it outdoors.

Colder temperatures can affect plants since they have the same temperature as the air around them. When they are exposed to the sun, they can start to get warm again, but this is not the case during winter. The temperature range for the Elaeocarpus japonicus is often 70~85℉(21~30℃). They might tolerate 20~30℉(-6~0℃) even 15℉(-10℃), but not for long since this can result in frost damage. Maximum temperatures should be around 70~85℉(21~30℃), but make sure that you spray them with water from time to time and give them some shade to prevent wilting.

Do some research and make sure that the temperature is right when growing Elaeocarpus japonicus. Some growers might consider decreasing the plants' thermostats during the growing season to reduce HVAC costs. However, it's vital to understand that the temperature can affect the flowering, pest management, and quality of the plants. There will be a temperature point where the Elaeocarpus japonicus will stop growing, and this can happen during the winter when some species might go into a dormant state. The base temperature becomes warmer when the season changes and the Elaeocarpus japonicus can grow faster. The species that are naturally growing in warm habitats have higher optimum temperatures when you compare them to the ones that thrive in a cooler climate. When the seeds of Elaeocarpus japonicus are exposed to cool temperatures, this can cause a decrease in uniformity and delays. You might also want to lower the temperature during flowering but not at other phases. Cooler temperatures at night will also require less water, so adjust the irrigation as needed.

Stop fertilizing the plant to avoid new growth and allow the old ones to become hardy. This way, they can endure colder temperature when it begins to drop. To keep them warm, you can build structures around the Elaeocarpus japonicus like cages or trellises. There are also options to use heat mats that can gently warm the soil since they can consistently maintain an ideal temperature range for the Elaeocarpus japonicus.

During winter, you can protect the Elaeocarpus japonicus from frost by covering it with cloths, tarps, burlaps, sheets, or plastic buckets. Make sure to keep them down so they continue to act as insulators and the wind will not blow them away. However, ensure that the plastic sheets or burlap covers should not touch any part of the fruit or foliage, or the cold temperatures can transfer to the material and cause burns. When the temperatures begin to rise during the daytime, remove the covers.

When growing the Elaeocarpus japonicus in spring, you might want to increase humidity since the air temperature tends to be cooler at this time. A dry temperature can be a stressful growing environment for various species, which can help. If summer arrives, the large cover of the greenhouse and the warm temperature will mean that there will be a higher humidity level in the air. Some signs to look for are the condensation that is often found on the walls of the greenhouse, and this can cause issues with pollination and the development of infections when the water begins to fall on the leaves. Make adjustments according to the temperature and do some spraying during the hotter days of the year.

Generally, the first cold snap can destroy the Elaeocarpus japonicus and others might go into a dormant state when the temperature is low. Some plants can get chilled when the temperatures range from 20~30℉(-6~0℃). They can freeze when the temperature begins to drop below 32℉(0℃). Those species that hide most of their parts under the soil might lose their structures above ground, but they can recover in spring. Some of the associated issues with too low temperatures are the lack of availability of resources like water, and nutrients, and those subtropical plants can suffer when the temperature reaches below 20℉(-6℃). The plants can also get damaged because of extreme heat stress when it's too high. This can reduce the transpiration rate that can affect the growth and productivity of Elaeocarpus japonicus.

You need to cover the plants at night since these can add about 5 degrees more to protect the species from frost and freezing temperatures. The cloth rows can work well as blankets and ensure that there are no openings where the heat could escape. When using the covers, avoid the plastic from touching the foliage because this can cause the Elaeocarpus japonicus to freeze. Remember to keep the covers during the day and stop using heat pads during the summer. It will always be worth the effort to protect the cold-intolerant plants from freezing temperatures to help them survive.

If you prefer not to use a heat pad, bring the Elaeocarpus japonicus inside, especially if it's freezing outdoors. During spring, consider the ones you need to bring indoors and plant them in moveable pots and containers.

Most often, the ones caring for the Elaeocarpus japonicus will grow them in greenhouses. This is because they can provide adequate temperature in these areas that won't affect the photosynthesis process of a specific process. Some install the proper HVAC systems to control the temperatures of Elaeocarpus japonicus. This can handle many species' cooling and heating needs, especially during the summer and winter. They generally place the cooling or heating pad under the plants rather than above to achieve their desired temperatures. If outdoors, you can protect the Elaeocarpus japonicus from frost by covering it with cloths, tarps, burlaps, sheets, or plastic buckets.

Heat mats are often left on Elaeocarpus japonicus to set the temperatures at a more consistent level. When the weather becomes warmer during the day, you can remove them, especially if the species are exposed to the sun. Put the pads away once the plants are established and when they start growing flowers and fruits.