Preparing the most resistant hibiscus plants for winter is quite easy to do, because these plants can live outdoors all year round, with minimal care. However, tropical hibiscuses should be kept indoors in all regions, with the exception of the warmer ones. Start with step 1 below to learn how to prepare both hardy hibiscus and tropical varieties for winter.
Steps
Part 1 of 3: Preparing the Hibiscus Planted in the Ground for the Winter
Step 1. Determine if the hibiscus plant is tropical or a resistant variety
Before making plans to prepare your hibiscus for winter, it is important to determine whether it is a hardy or tropical variety. Hardy varieties can survive outdoors during the winter in areas with a climate index above 5 (see Tips section for more information), but tropical varieties will need to be transplanted into a pot and moved indoors once temperatures drop below 10 ° C.
- Tropical varieties typically have dark, glossy leaves and small flowers. The flowers are most likely two-colored, but there are some varieties with single-colored flowers. Temperatures below 4 ° C will prove fatal for these plants.
- Hardy hibiscuses have rougher, duller leaves and very large flowers. They are more resistant to cold temperatures than tropical varieties.
Step 2. Feed the hibiscus with a potash fertilizer in late autumn until the beginning of winter
Feed the hibiscus plant with a potash fertilizer in October or November to encourage abundant flowering the following year.
Do not give it nitrogen during this period - nitrogen will encourage new growth of leaves that will only be damaged by cold weather or will fall off during the winter
Step 3. Take care of the hibiscus plant during the autumn months
Water the hibiscus generously once a week, or two if it's not raining. Eliminate falling leaves and other unnecessary material from stems to help prevent disease.
- These few additional steps in the fall will help the plants bounce back in the spring to thrive again with lush green foliage and beautiful flowers.
- After mulching the soil, you no longer have to do these activities.
Step 4. Apply a consistent layer of mulch in the soil around the plant
The thick layers of mulch will protect the hibiscus from any unexpected temperature changes. Adding a layer of compost under the mulch can also help protect these plants.
- Spread organic mulch over the root area to a height of 5-7.5 cm, but keep the mulch a few inches away from the stems.
- If there is already mulch around the hibiscus, loosen the mulch with a rake and add new mulch, if necessary, to have a total layer of 5 to 7.5 cm in height.
Step 5. Protect the hibiscus plants from frost
The effects of very cold temperatures can be partially mitigated by using frost protection fabrics. In areas that are not affected by severe frosts, plants can be protected during unusually cold winters by using Christmas tree lights strung on the plant, plugging them into the nearest outlet.
These lights can be used in addition to frost protection fabrics or can be used alone
Step 6. Transplant the tropical hibiscus in pots
If your tropical hibiscus is planted in the ground, you need to transfer it to a large container so that it can spend the winter indoors. Use soil for growing houseplants when decanting, avoiding garden soil.
To dig the hibiscus, push the shovel into the ground 6 to 8 inches away from the stems to cut off the root branches all around the hibiscus. Then lift it with the tip of the shovel
Part 2 of 3: Preparing the Hibiscus Grown in Pots for the Winter
Step 1. Check container-grown hibiscus for any signs of infestation
Gardeners should carefully check their container-grown hibiscus for signs of insects a few days before temperatures begin to drop.
If you notice pests, you should apply a suitable pesticide. This is best done a few days before bringing the hibiscus indoors, especially if there are family members prone to allergies
Step 2. Wash the plant before bringing it indoors
It is a good idea to wash the plants a couple of times outside before bringing them indoors. This helps get rid of any insects that may be lurking in the foliage, as well as any dirt or pollen that may still be on the leaves.
Cleaning the hibiscus container with a damp cloth will also help reduce the amount of soil and allergens that are brought inside
Step 3. Fertilize the plant
Adding a slow-release fertilizer such as Osmocote to the plant can be useful, before bringing it indoors, because regularly fertilized hibiscus plants will recover more quickly in spring.
Step 4. Prune the hibiscus plant to make it more manageable
Plants that have grown a lot may need to be pruned before winter. Hibiscus plants generally tolerate strong pruning, so trimming them to give them and to keep their shape shouldn't be a problem.
- As hibiscus bloom on new stems, fall pruning will help them bloom more abundantly in the following spring / summer.
- To get even more flowers, tear off the tips of the new stems after they have reached a length of about 20 centimeters, and again when they reach a foot or so. Plucking the tips will encourage more branching, resulting in an abundance of new stems and flowers.
Part 3 of 3: Taking Care of Hibiscus Inside
Step 1. Check the instructions for caring for your specific hibiscus variety
Once indoors for the winter, the hibiscus still needs proper care if you want it to survive the following months. Gardeners are advised to take care of the plant they have, and treat it accordingly, rather than trial and error.
However, if the plant's label has been lost or if the plant has been received as a gift, this article will provide some tips that apply to most hibiscus
Step 2. Provide the hibiscus with heat and / or light
Hibiscus needs heat and light to bloom indoors, but will prefer warmth to light if forced. Ideally, these plants should be placed next to a window in the warmest and most comfortable location possible.
- Plants that spend their winters in a windowless room, or one that has poor lighting, will benefit from a lamp. However, gardeners should take care to keep the device far enough away from plants to avoid burning them.
- Hibiscus kept in attached units (garages, storerooms and the like) will likely need a heating system of some kind, to keep them warm enough to survive, however even a tiny heater will adequately serve this purpose.
Step 3. Keep the temperature above about 13 ° C if possible
Tropical plants generally prefer a temperature above 13 ° C; however, tolerance to cold varies by species, and gardeners will need to check their plant's specific needs.
Step 4. Prevent the leaves from discoloring
Direct sunlight is recommended for most hibiscus species, but some may require a little less. If the leaves of the plant begin to appear brown or discolored, it may be better to move the hibiscus to a place with less light.
Step 5. Make sure the soil is kept moist
Water the hibiscus according to the specific needs of the different varieties. Eg:
- In winter, Chinese hibiscus (Hibiscus rosa-sinensis) will only need to be watered enough to prevent the soil from drying out, while mallow cultivars (Hibiscus moscheutos) will require moderate levels of humidity.
- Gardeners must be aware that mallow varieties cannot tolerate a lack of water or even excess water.
Advice
- Gardeners should keep in mind that hardy hibiscus can survive the winter outdoors in areas with a climate index above 5, but that outdoor plants can go dormant in some areas. Tropical hibiscuses can be left outdoors in areas with a climate index above 9 or 10. These are some tips that will help you keep plants alive during the colder months.
- Climate zones refer to standard indices as defined by the US Department of Agriculture. Check these indexes to establish correspondence with the area where you live.
