With its bright red funnel flowers, the indoor hibiscus creates small islands of opulence on the windowsill. Magnificent cultivars with white, pink, yellow or two-tone flowers with a diameter of up to 10 centimeters provide color variety. Hobby gardeners who respond to their needs will be rewarded with a hibiscus rosa-sinensis with continuous flowering almost all year round. In addition to an adequate supply of water and nutrients, the focus here is on professional pruning, because the mallow plant grows up to 3 meters high in the wild. The following lines explain in detail how to care for a hibiscus as a houseplant.
Table of Contents
Characteristics
- Plant family of Malvaceae
- Genus Hibiscus (Hibiscus)
- Species Chinese rose mallow (Hibiscus rosa-sinensis)
- Evergreen shrub of tropical origin
- Growth height 100 to 300 centimeters
- Funnel-shaped flowers, up to 10 centimeters in diameter
- Flowering time from February to October
- Green leaves up to 9 inches long and 5 inches wide
- Main use as an ornamental shrub
Thousands of varieties of the hibiscus rosa-sinensis are cultivated worldwide. While in Europe an indoor hibiscus is used exclusively for decoration, people in Asia use its flowers and leaves to eat them as a treat.
location
As a tropical plant, the indoor hibiscus prefers a bright window seat with mild morning or evening sun. The ornamental plant wants to be protected from the blazing midday sun so that its magnificent flowers and shiny leaves do not burn. If you like to spend the nice time of the year on the balcony and terrace, a hibiscus rosa-sinensis will be happy to keep you company. The flowering shrub feels most comfortable in a partially shaded, sheltered place. After a gradual acclimatization phase of 8 to 10 days to direct sunlight, the plant accepts a full sun position during the summer.
- In room culture, rose mallow thrives at normal room temperatures between 18 and 28 degrees Celsius
- The move to the balcony and the terrace only takes place from a constant 15-18 degrees and higher
Hibiscus rosa-sinensis is known to be extremely site-loyal. This implies that he doesn’t want to be carried back and forth all the time. If the plant moves from the room to the balcony, it is advisable to select the summer location beforehand. If it gets too turbulent for the rose mallow, it will drop its blossoms and buds without warning. This also applies when the houseplant clears its place on the windowsill because the glass panes are being cleaned. In this case, mark the side of the pot facing the sun so that you can then put the room hibiscus back up in the same way.
humidity
In order for a room hibiscus to develop its full splendor, it needs the highest possible humidity of more than 60 percent. In order to be able to guarantee this value in rooms, various methods are available:
- Fill the coaster with pebbles and water so that any moisture that evaporates constantly rises
- Set up water-filled bowls in the room
- A babbling indoor fountain keeps the humidity at a high level
- Commercial air humidifiers are not only good for indoor hibiscus
In addition, the houseplant enjoys a gentle shower from the hand sprayer. To prevent unwanted limescale from forming on the leaves, we recommend using collected rain or decalcified tap water. Never surprise the indoor hibiscus with ice-cold water straight from the tap. In the worst case, the sensitive flower reacts to such a temperature shock by shedding its blossoms.
watering and fertilizing
The Chinese rose mallow has a high water requirement. This circumstance requires a regular thumb test to determine the moisture content of the substrate. Press your thumb a few inches into the soil. If it feels dry, water it. If there are no pebbles in the saucer, the excess water is removed after 30 minutes. As much as a hibiscus rosa-sinensis loves a moist environment, it reacts very quickly to waterlogging with root rot. If, on the other hand, the substrate dries out too much, the houseplant will shed all the buds without further ado.
A typical feature of the rose mallow is the high nutrient requirement. To ensure that the flowering shrub has the energy it needs for a long flowering period, it should be fertilized regularly. We recommend a weekly dose of liquid fertilizer for flowering plants in the period from February to August/September. If no winter rest is planned for the indoor hibiscus, the nutrient supply continues in an extended rhythm of 2 to 3 weeks. Otherwise, stop fertilizing in late summer so that the plant can prepare for the coming hibernation. In this case, all existing shoots have enough time to mature before winter.
hibernate
If you allow your indoor hibiscus to hibernate from October to February, the lifespan will be noticeably longer. The specific hibernation is not absolutely necessary, because a year-round cultivation at the window seat is not excluded.
- Place indoor hibiscus in a light spot throughout the winter, but away from full sun
- Temperatures of 13 to 15 degrees Celsius are ideal
- Water only a little and do not fertilize
An indoor hibiscus does not develop flowers during the winter break, so that it can gather strength for the next season. The Chinese rose mallow should not be placed cooler than 13 degrees Celsius, otherwise it will drop all its leaves. Given the very slow growth rate of this plant species, it is questionable whether it will develop a sufficient number of leaves in time next spring to provide the much-desired flowers.
repot
An indoor hibiscus should be repotted immediately after purchase. As a result, the flowering plant changes the tub every two years until it is fully grown. A high-quality potting soil based on compost is recommended as a substrate, the permeability of which is improved with a handful of sand. Optionally, you can mix your own individual potting soil from components such as loamy garden soil, plenty of humus, perlite, orchid soil, compost and sand.
- Spring is the best time to repot indoor hibiscus
- The new flower pot is a maximum of 1-2 centimeters larger
- There is a water drain in the floor
- Above this is a drainage made of coarse, mineral material
Fill the bucket one third with substrate and then place the potted room hibiscus in the middle. While you fill in the rest of the substrate, press it down a little with your fist. In this way, no air bubbles form that could inhibit root growth. It makes sense to leave a pouring edge of about 2 centimeters free. Then generously water the repotted rose mallow.
To cut
If you buy a hibiscus rosa-sinensis as a houseplant, it impresses with a compact, dense habit. However, the plant does not develop this appearance naturally. Garden centers and breeders use chemical compression preparations for this purpose so that the hibiscus does not grow so sparsely that nobody wants to buy it. Over time, the effect of these agents decreases, so that regular trimming is now required at the latest. Since hibiscus always blooms on the one-year-old shoots, early spring is ideal for this care measure. The fresh shoots should not have started yet.
- Thin out the flowering bush thoroughly
- Remove all dead wood, dried leaves and flowers
- Shorten the houseplant altogether down to 15 centimetres
- A cut in the old wood is accepted
- An oblique incision is advantageous
- Start each cut 2-3 millimeters above a bud
In the course of the growing season, the houseplant is cleaned regularly. This means that wilted flowers and dried out foliage are removed. This not only looks neater, but also encourages your rose hibiscus to bloom again.
multiply
In view of the heavenly beauty of a hibiscus rosa-sinensis, the desire for more specimens is hardly surprising. Self-respecting hobby gardeners dare to propagate themselves. If you would like to grow an indoor hibiscus with exactly the attributes of the mother plant, the use of cuttings is a good idea. This method is uncomplicated and does not require extensive experience. Alternatively, sowing is an option if you want to grow a new or alternative variety.
cuttings
In early spring, select one or more vigorous, healthy cuttings. Ideally they come from a one or two year old shoot and are not fully woody. With a clean cut just below a bud, cut each cutting to a length of 15 centimeters. Then half of the branch is defoliated. The procedure continues in the following steps:
- Cultivation pots fill with nutrient-poor cultivation substrate
- Insert half or two thirds of a cutting into it and moisten it
- Place in a heated indoor greenhouse in a partially shaded location
- Alternatively, put a plastic bag over each pot, supported with chopsticks
The ideal temperature for rooting is a constant heat of 25 degrees Celsius. In addition, a high level of humidity must be ensured by regularly spraying the substrate and cuttings with lukewarm rainwater. The growing area is ventilated for a few minutes every day to prevent mold from forming.
With regard to the duration, no general statement can be made. An indoor hibiscus takes between 3 weeks and 3 months to develop an independent root system. As a sign of a successful cutting propagation, keep an eye out for roots growing out of the potty drain or for a tender shoot at the tip of the cutting. When the time comes, repot the young plant into a new container, which is now filled with normal substrate for hibiscus rosa-sinensis.
sowing
To get the hard-shelled hibiscus seeds ready to germinate, soak them in lukewarm water for 24-48 hours before sowing. It has proven helpful to roughen each seed a little with sandpaper. After the pre-treatment, proceed as follows:
- Fill small pots with seed soil and plant one seed in each
- Sieve thinly with substrate and spray with lime-free water
- Cover cling film or place the jars in a mini greenhouse
Under the influence of a constant temperature of 26-30 degrees Celsius, combined with high humidity, germination begins within 1-2 weeks. When growth has progressed so far that two to three pairs of leaves have developed, repot the seedlings into normal hibiscus substrate. A cover is no longer required so that the young plants get used to the normal indoor climate. From 2 months of age, the normal care protocol begins, including a first dose of liquid fertilizer.
Conclusion
An indoor hibiscus is far less demanding when it comes to care than the lush flowering bush might imply at first glance. If aspects such as a light location, enough water and a balanced supply of nutrients are taken into account, a hibiscus rosa-sinensis thrives very well as a houseplant. So that it doesn’t grow too much for you after a while, a courageous pruning should be noted in the care program every spring.
