Hypericum moserianum is an evergreen, herbaceous plant that is native to the Balkan Peninsula. The leaves are opposite, ovate to lanceolate, and measure 25 cm long and 12 cm wide. The flowers are yellow, with 5 petals and 10 stamens, and appear in July and August. The fruit is a capsule that contains numerous small seeds.
Related plant:
Hypericum Shrub
About soil condition, hypericum moserianum needs well-drained soil, and prefer sandy or gravelly, neutral to slightly alkaline soil. They are not very fussy about soil type as long as it is not waterlogged.
Like the other Hypericum species, Hypericum moserianum enjoys full sun to partial shade. In fact, it thrives in sunny locations and produces the most flowers when it gets plenty of sun. However, it will also tolerate some shade, especially in hot summer climates. It's a good idea to give this plant a little afternoon shade in hot weather to prevent the flowers from fading.
The temperature condition that is most favorable for the growth of Hypericum moserianum is a temperature range of 20 to 25 degrees Celsius. This temperature range is optimal for the growth and development of this plant species. Above or below this temperature range, the growth of Hypericum moserianum is significantly inhibited.
Ideal humidity condition for this plant is 50% or less. While 50% humidity is the ideal, this plant can tolerate up to 60% without any problems. If the humidity gets any higher than that, the leaves will start to turn yellow and drop off.
For the fertilizer, this family of plant is not too particular and anything from 5-10-5 to 10-10-10 will work just fine. The best way to apply the fertilizer is to scatter it around the base of the plant and then work it into the top couple of inches of the soil. As for the roots, they like to be well-drained and on the sandy side so if your soil is on the heavy side, you might want to consider adding some sand to the planting hole.
Pruning your Hypericum Moserianum is essential to keeping the plant healthy and strong. Remove any dead or dying branches as well as any branches that are crossing over each other. This will help to promote new growth and keep the plant looking its best.
Propagation of Hypericum moserianum is typically done through seed, although cuttings can also be taken from new growth. Seed should be sown in a sterile, well-draining medium and kept at a temperature of 18-21°C (65-70°F). Cuttings should be taken from new growth, using a sharp knife or pruners, and rooting hormone can be applied to the cut ends to encourage root development. Cuttings should be placed in a sterile, well-draining medium and kept at a temperature of 18-21°C (65-70°F).
Usually, the plant growth rate is about 5 to 10 centimeters a year. However, some individuals may grow at about 2.5 centimeters a year while others may grow rapidly at about 15 centimeters a year. The average size of a mature hypericum moserianum is about 30 centimeters.
Common problems for this kind of plant are lack of flowering, excessive leaf drop, and dieback. To encourage flowering, give the plant plenty of sunlight and well-drained soil. To reduce leaf drop, water the plant deeply but infrequently. And to prevent dieback, prune the plant regularly to encourage new growth.
Source:
Hypericum New Use Ag
Hypericum Androsaemum | NC State Extension
Hypericum 'Hidcote' | Landscape Plants | Oregon State University