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 Willow-leaf lance fern 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 Willow-leaf lance fern. 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 Willow-leaf lance fern 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 Willow-leaf lance fern 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 Willow-leaf lance fern 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 Willow-leaf lance fern 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 Willow-leaf lance fern.

During winter, you can protect the Willow-leaf lance fern 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 Willow-leaf lance fern 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 Willow-leaf lance fern 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 Willow-leaf lance fern.

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 Willow-leaf lance fern 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 Willow-leaf lance fern 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 Willow-leaf lance fern 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 Willow-leaf lance fern. 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 Willow-leaf lance fern from frost by covering it with cloths, tarps, burlaps, sheets, or plastic buckets.

Heat mats are often left on Willow-leaf lance fern 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.