It is a genus that includes about fifteen species of terricolous orchids, with deciduous leaves, widespread in Australia, New Zealand and Indonesia; they have large tuberous roots, which tend over time to produce numerous shoots with new plants; each tuber produces a single leaf, semi-erect, elongated, of gray-green color, in many species quite fleshy. In spring and summer from each tuber stands a stem bearing single flowers, or more often gathered in long panicles, 40-50 cm high, which bear 10-20 flowers, generally blue or purple, but also red, yellow or whites. In most species the labellum is completely similar to the other petals. Orchids of not easy to find, very widespread, however, in the area of origin and with very particular colors.
Place the Thelymitra orchids in a very bright, even sunny position; the thelymitra are called sun orchids, since their flowers bloom only on bright and sunny days, while they close at night or in the presence of clouds when the sunlight disappears. These orchids can withstand minimum temeprature close to 4-5 ° C, in areas with harsh winters it is therefore good to keep the tubers in a cold greenhouse; with the arrival of autumn cold the aerial part dries completely, if we live in areas with not very cold winters we can simply protect these plants with a good mulching of the soil.
As for watering, regularly irrigate the Thelymitra orchids, avoiding to leave stagnations in the saucer and letting the soil dry well between one watering and another to avoid precisely the formation of root rot; From March to September, provide specific fertilizer for orchids every 10-15 days, mixed with the water used to ensure optimal growth. It is advisable to reduce the amount of fertilizer to be administered to the plant compared to what is written on the package. A little product is enough to greatly improve the growth of the orchid.
The soil is a fundamental element to consider for the growth of our plants. Thanks to the soil, our orchids can acquire the nutrients they need to develop. For this reason, the choice of the soil must be weighted and realized based on the specific needs of our plants. As for the soil, therefore, use a good balanced universal soil, rich in organic matter, lightened with a few pieces of bark and with a minimum quantity of sand or perlite. The tubers tend to widen, therefore the specimens grown in pots should be repotted every 2-3 years, to provide enough space for the roots to develop.
The multiplication of this orchid generally occurs by seed; in autumn it is also possible to divide the tubers, taking care to leave some well-developed roots for each portion practiced.
Thelymitra: Pests and diseases
In general this orchid does not fear the attack of pests or diseases. Beware of water stagnation and the formation of radical rot that could compromise the development of the plant.