When watering the Mexican sunflower, you should aim to use filtered water that is at room temperature. Filtered water is better for this plant, as tap water can contain particles that are harmful to its health. The reason that the water should be at room temperature or slightly warmer is that the Mexican sunflower comes from a warm environment, and cold water can be somewhat of a shock to its system. Also, you should avoid overhead watering for this plant, as it can cause foliage complications. Instead, simply apply your filtered room temperature water to the soil until the soil is entirely soaked. Soaking the soil can be very beneficial for this plant as it moistens the roots and helps them continue to spread through the soil and collect the nutrients they need.

Both overwatering and underwatering will be detrimental to the health of your Mexican sunflower, but overwatering is a far more common issue. When this species receives too much water, its stems and leaves may begin to wilt and turn from green to yellow. Overwatering over a prolonged period may also lead to diseases such as root rot, mold, and mildew, all of which can kill your plant. Underwatering is far less common for the Mexican sunflower, as this plant has decent drought tolerance. However, underwatering remains a possibility, and when it occurs, you can expect to find that the leaves of your Mexican sunflower have become brittle and brown. It is crucial that you notice the signs of overwatering as soon as possible when caring for your Mexican sunflower. Some of the diseases that arise from overwatering, such as root rot, may not be correctable if you wait too long. If you see early signs of overwatering, you should reduce your watering schedule immediately. You may also want to assess the quality of soil in which your Mexican sunflower grows. If you find that the soil drains very poorly, you should replace it immediately with a loose, well-draining potting mix. On the other hand, if you find signs that your Mexican sunflower is receiving too little water, all you need to do is water more regularly until those signs have subsided.

If your plant is in a pot. The most precise way to decide whether your Mexican sunflower needs water is to plunge your finger into the soil. If you notice that the first two to three inches of soil have become dry, it is time to add some water. If you grow your Mexican sunflower outdoors in the ground, you can use a similar method to test the soil. Again, when you find that the first few inches of soil have dried out, it is time to add water. During the spring and early fall, this method will often lead you to water this plant about once every week. When extremely hot weather arrives, you may need to increase your watering frequency to about twice or more per week. With that said, mature, well-established the Mexican sunflower can show an admirable ability to withstand drought.

When it comes time to water your Mexican sunflower, you should not be shy about how much water you give. With the first two to three inches of soil dry, this plant will appreciate a long and thorough watering. Supply enough water to soak the soil entirely. The amount of water you add should be enough to cause excess water to flow through the drainage holes at the bottom of your pot. If you don’t see excess water draining from the pot, you have likely underwatered your plant. But do not let the water accumulate inside the soil, which will be very dangerous to the plant as well. Alternatively, a lack of water draining through the pot could indicate poorly draining soils, which is detrimental to the health of this plant and should be avoided. If the plant is outside, 1 inch of rain per week will be sufficient.

The water needs of the Mexican sunflower can change depending on growth stages as well. For example, when your Mexican sunflower is in the first few years of its life, or if you have just transplanted it to a new growing location, you will need to give more water than usual. During both of those stages, your Mexican sunflower will put a lot of energy towards sprouting new roots that will then support future growth. For those roots to perform their best, they need a bit more moisture than they would at a more mature phase. After a few seasons, your Mexican sunflower will need much less water. Another growth stage in which this plant may need more water is during the bloom period. Flower development can make use of a significant amount of moisture, which is why you might need to give your Mexican sunflower more water at this time.

The Mexican sunflower will have its highest water needs during the hottest months of the year. During the height of summer, you may need to give this plant water more than once per week, depending on how fast the soil dries out. The opposite is true during the winter. In winter, your plant will enter a dormant phase, in which it will need far less water than usual. In fact, you may not need to water this plant at all during the winter months. However, if you do water during winter, you should not do so more than about once per month. Watering too much at this time will make it more likely that your Mexican sunflower will contract a disease.

It is most common to grow the Mexican sunflower indoors for any gardener that does not live in temperate and tropical regions. Those gardeners should consider the fact that soil in a container can dry out a bit faster than ground soil. Also, the presence of drying elements such as air conditioning units can cause your Mexican sunflower to need water on a more frequent basis as well. if you planted it outside. When that is the case, it’s likely you won’t need to water your Mexican sunflower very much at all. If you receive rainfall on a regular basis, that may be enough to keep your plant alive. Alternatively, those who grow this plant inside will need to water it more often, as allowing rainwater to soak the soil will not be an option.

Mexican sunflower typically needs at least six to eight hours of direct sunlight every day. If you are growing your plant outdoors, make sure to choose a spot that receives full sunlight throughout the day. If you are growing your Mexican sunflower indoors, try to place it near a south-facing window or another location that receives plenty of sunlight. While Mexican sunflower needs full sunlight to grow and thrive, it’s essential to avoid exposing them to direct sunlight during high temperatures, such as over 35°C(95℉) or during hot summer afternoons. If the sunlight is too intense, it can cause the leaves to become scorched or wilted. To avoid this, you can consider using sheer curtains or blinds to filter the sunlight or moving the plant to a shadier spot.

If your Mexican sunflower doesn't receive enough sunlight, it may struggle to grow and may become weak and leggy. The leaves may also start to turn yellow, indicating that the plant is not getting enough sunlight to produce chlorophyll. In extreme cases, the plant may even die.

While Mexican sunflower needs full sunlight, it’s crucial to avoid exposing it to too much direct sunlight. If the plant is exposed to intense sunlight for an extended period, it can start to show signs of sunburn, such as brown or scorched leaves. To avoid this, make sure to monitor the plant and move it to a shadier spot if necessary.

For this tropical plant to thrive, you’ll want to keep them between 75℉ and 90℉ (25-32℃). Each species can handle temperatures outside of this range, but keeping it within several degrees of these limits will ensure they grow to their maximum potential. As for its extreme temperature limits, any environment below 50℉ (10℃) or above 95℉ (35℃) will begin to hinder its growth and cause various aberrations to its leaves and stems. This is especially true with low temperatures; even a light frost can cause your tropical plants to perish. Cellular death can begin to happen at a rapid pace, with some species dying in as little as 12 to 24 hours.

While Mexican sunflower doesn’t require any changes in temperature to enter different growing phases, it is important to stay consistent. Wild temperature fluctuations can slow down its growth regardless of its current phase, so it's always better to keep them in a controlled environment. That optimal temperature range of 75℉ and 90℉ (25-32℃) is vital to maintain, especially staying above the lower limit. Going above 90℉(32℃) isn’t ideal, but as tropical plant it won’t suffer too much. On the other hand, going below 50℉ (10℃) (and especially 40℉/5℃) will begin to directly damage this heat-loving plant species.

Mexican sunflower does not need different temperatures for different growing seasons. The most important step in seasonal care is to keep the environment within the optimal temperature range. That's why it's always best to keep this plant indoors. That way, you can control the temperature no matter what the climate is like outside. Light is also important for tropical species, with all of these plants preferring a partial side level of sun exposure. This means any light they receive needs to be dappled or filtered, with bright but indirect light being the best option when growing your plants indoors. Too much direct sunlight can negatively affect your plant’s leaves, reducing its growth potential.

Tip #1: Don’t Leave Your Plant Near Windows in Colder Months If you want to make sure your plant isn’t exposed to colder temperatures, you may want to keep them away from windows. In colder months like late fall and winter, even the smallest draft can leak cold air into your home through cracks in your windows. While this air usually dissipates and warms up as it travels throughout your home, any plants placed in close proximity to the window will be affected. Move your tropical plants into an area where they will still get bright but indirect light, while making sure they won’t be affected by potential drafts. Tip #2: If You Find Dry Patches, Your Plant May Be Getting Too Much Sunlight or Heat You may notice the leaves become white or even scorched on a sunny day. These discolorations and unusual markings usually indicate that a plant is getting too much heat or sunlight, and it may be dehydrated. Excess light and heat will dry out the soil, stopping plants from getting the moisture they need to support their cellular structure. It also slows down or stops the process of photosynthesis, further hindering growth. If ignored for too long, these dry spots can spread and eventually result in the death of your plants. Tip #3: Avoid Frost at All Costs Colder temperatures and frost can damage your plants by causing ice crystals or disrupt normal physiological activity. This makes it nearly impossible for water to move freely throughout plant tissue, creating a deficit of moisture in their stems and leaves. You can tell a plant has been damaged by frost if it begins to suffer from hydrosis (it will appear as though it's soaked with water.) If the problem persists, your plants may begin shriveling and turning a dark brown or black hue. After that, the plant will almost certainly die.

The best way to maintain the right temperature range for Mexican sunflower is by keeping an eye on both the climate and humidity. You’ll want to try to keep each species in a room where you have access to climate control, keeping the heat in the temperature range best mimics its natural habitat. The humidity levels will also have a direct effect on temperature, so it's important to monitor these as well. You can artificially raise the humidity of your growing space by using a humidifier or lightly misting the leaves with water. If you intend to grow this species outside, you may find it difficult to maintain the right balance of temperature and humidity. If temperatures begin to drop or the air becomes too dry, your best option is to find room within your home and move your plant inside. An indoor growing space will allow you to control the climate more closely, helping your plant reach its full potential.