How the yellow colour is made
While green, white and red are set by leaf maturity at harvest and the drying method, yellow is the result of one more step: already-dried green or white leaf is dried and cured for even longer or in a special way, sometimes under controlled humidity (a light fermentation), sometimes by blending leaf dried in different ways. This shifts the hue towards golden yellow. The method is not standardised and differs from producer to producer, so quite different powders can sit under the same "yellow" name.
What the plant is
Whatever the colour, it is still the leaf of the same tree, Mitragyna speciosa - an evergreen tropical tree of the coffee family (Rubiaceae), a botanical relative of coffee from the humid forests of Southeast Asia (where kratom grows). The leaf holds more than forty alkaloids; the main one is mitragynine, alongside smaller amounts of 7-hydroxymitragynine, speciogynine and paynantheine. How much of them a powder holds is set not by the colour but by the specific batch: it is measured by the accredited VŠCHT Prague laboratory by HPLC, along with purity, microbiology and heavy metals (how to read a COA).
Yellow for balance? What may be said about effects
Yellow is often assigned a "balanced" or transitional role between green and red. The psychomodulatory substances act forbids a seller from stating effects, and there is no basis for such labels: the alkaloid ranges of the colours overlap and it all comes down to the batch. The only permitted wording about effects is the mandatory information on the pack. What the law and science say is summarised in Kratom effects: what we may say.
What our range is built on
We carry three colours whose processing is unambiguous and can be documented batch by batch: green (medium maturity, ordinary drying), white (younger leaf, drying without sun) and red (mature leaf, the longest drying or a short fermentation). The strains are on the Maeng Da, Sumatra, Thai, Elephant and Rurut pages; the forms are described by powder, nano and extract. What is currently in stock is shown in the catalogue above.
Colours we carry, and strains
Vein colours in this range: Green, White, Red.
Other strains: Maeng Da, Sumatra, Thai, Elephant, Rurut.
Warning: This product is not a food. Not intended for persons under 18. Use according to the instructions. Do not exceed the recommended daily dose.