A Detailed Guide to Calceolaria Cultivation: Learn How to Grow Healthy, Radiant Calceolaria
How do you grow Calceolaria? Calceolaria is afraid of both cold and heat, afraid of both drought and dampness, loves sunlight yet tolerates shade, and at the same time dislikes direct blazing sun, so it is harder to cultivate than ordinary herbaceous flowers. Below, let us introduce the cultivation methods for Calceolaria.
1. Soil requirements
It requires a loose, well-aerated, freely draining sandy loam rich in humus, plus a small amount of bone meal as a base fertilizer; it should be sterilized at high temperature before use.
2. Temperature requirements
The optimum growing temperature for Calceolaria is around 15°C. When it is higher than 20°C, growth, bud formation and flowering are affected. If the temperature can be lowered to around 10°C during flowering, the flowering period can be extended. However, the nighttime temperature during the growing period and the overwintering temperature must not fall below 10°C.
3. Light conditions
It likes light but dislikes direct blazing sun. When the light is too strong at midday, it should be shaded appropriately and kept well ventilated, otherwise damping-off is easily caused; increasing the light duration can bring flowering forward. For example, if 3 hours of light are added each day starting in November, it can bloom by the end of January the following year; for greenhouse cultivation, note that 30% shading should be applied before October, no shading from October to March of the following year, and about 50% shading during the flowering period after March.
4. Water requirements
Drought will cause poor growth of the plant, so attention must be paid to drainage; excessive moisture easily causes root rot. When watering, do not splash the leaves, because the leaf surface is hairy and the leaves rot easily. Watering should follow the principle of watering when dry and stopping when wet; you can often sprinkle water around the flowerpot to keep the air humidity above 80%, but note that during the flowering period you must not spray water on the flowers, so as not to affect seed setting.
5. Fertilizer requirements
It likes fertilizer, but it should not be too concentrated. During the growing period, apply a dilute, well-rotted cake fertilizer solution or hoof and horn chip liquid fertilizer once every half month; be sure to avoid fertilizer water splashing the leaves, which can make the flowers abundant and the leaves lush. If leggy growth of stems and leaves is found, stop fertilizing immediately; when repotting, mix an appropriate amount of rotted fertilizer into the potting soil; when flower spikes appear, apply a 1% calcium superphosphate solution 2 times to make the flower colors more vivid.
6. Pollination requirements
Natural pollination of Calceolaria is difficult, so for seed collection, artificial pollination should begin at the start of the flowering period, consciously carrying out selection and hybridization. This should generally be done in the morning. After pollination, the corolla can be cut off; at the same time, strengthen shading and ventilation, avoid direct sunlight, and keep the potting soil slightly dry. This can increase the seed-setting rate and produce fuller seeds.
7. Propagation methods
Calceolaria propagation generally uses sowing, carried out at the end of August and the beginning of September when the weather is cool. If sown too early, the hot weather makes damping-off easy; if too late, the plants are small, affecting flowering the following spring. For sowing, it is best to use a sterilized, rotted leaf mold mixed evenly with fine sand as the potting soil. After sowing, cover with a layer of screened fine sand, just enough to cover the seeds. After sowing, water by the soak-pot method, cover the pot surface with glass, place in a shady spot, and keep at around 20°C. Seedlings emerge in about half a month. After emergence, remove the glass 3 days to 5 days later, place in a ventilated spot with light, and thin the seedlings in time. Lower the temperature to 15°C. The potting soil must not be too dry or too wet; pay attention to increasing air humidity. When 2 to 3 true leaves have grown, transplant into small pots. In November to December, when there are 8 leaves, they can be planted individually in large pots. The room temperature should be 8°C-12°C, and they can bloom from February to April the following year.
From the above introduction, everyone should now have an understanding of Calceolaria cultivation methods. For friends who want to grow Calceolaria, I hope the above methods can help you!