Hark Orchideen - FAQ


We would like to answer some frequently asked questions about the production process and also inform you on in vitro propagation of orchids.

What does in-vitro mean?
In vitro comes from Latin and refers to production in glass. In plant tissue culture, plant cells or parts of plants are cultivated in sterile conditions on liquid or solid culture media.

The explants taken from the plants for propagation are sterilized and then cultivated on sterile culture media. Today, however, sterile plastic cups are generally used instead of glass as the production vessel.
What are the advantages of in-vitro progagation of orchids?
Mass propagation of orchids, in particular the propagation of Phalaenopsis, is not possible without tissue culture. Therefore, professional cultivation of Phalaenopsis and other orchids worldwide could only be done with the methods of in vitro propagation. Up to this point only seedlings were cultivated on sterile culture media.

Today, seedlings are still produced, but exclusively for breeding purposes. Plants selected by breeding can then be propagated in large numbers in vitro. Tissue-cultivated plants offer various advantages over seedlings. For example, these plants are very homogeneous because each plant is identical to the selected parent plant. This gives the grower a uniform plant stock with the same growth and flowering characteristics. This means that the plants are pure and can be supplied continuously. Furthermore, the cultivation risk is reduced by healthy starting material.

All plants are tested for possible virus infestation and are free of other diseases due to the sterile production conditions. HARK is one of the first companies worldwide to propagate orchids in vitro.
Meristem – what is that?
Meristem is an undifferentiated tissue that is constantly dividing. These cells are located at the tips of shoots, on side shoots or at the root tips. Since these cells are undifferentiated, all organs of the plant, such as leaves, flowers or roots, can develop from them.
How does in vitro production of phalaenopsis work?
In in vitro production of Phalaenopsis we can distinguish the following phases:

- Starting phase: Transfer of plant explants into sterile conditions. During this process the removed meristems are sterilized to ensure that no germs can enter the culture media.

- Stem phase: Setup of mother plant cups for the production. From the initial phase, the plants are pricked into the so-called stem cups. By adding phytohormones, the plants start to form side shoots. During stem formation, these shoots are then separated with a scalpel and used again for the further construction of stem cups. This production method is also called shoot by shoot.

- Final phase: Large, vigorous plants from stem propagation are transferred into fresh cups with rooting nutrient medium. When the plants have developed strong roots and large leaves, the product is ready to be sold. The next step is acclimatisation, i.e. from in-vitro the plant is cultivated ex-vitro in ground plugs in greenhouses.
Does HARK also produce other plants in the laboratory?
For years now, we have been increasingly dealing with other cultures that can be propagated in a laboratory in addition to our core business. Please contact us for further information.
Can orchid lovers also purchase plants from hark?
We manufacture and sell our products exclusively to professional young plant and production companies worldwide.
How many young plants are in one single cup?
There are 26 plants (25 + 1 plant as an addition for possible failures) in one single cup for the Phalaenopsis Classic Line, 30 plants (28 + 2 plants as an addition for possible failures) for the Basic Line, 40 plants for multigenous hybrids and sowing.
Is it possible to purchase selected varieties from HARK's assortment?
With a minimum order of 5,000 plants per clone and year, varieties from our assortment and the assortment of our selected partners can be ordered as tissue culture plants in a cup. We can supply rooted young plants via our Dutch young plant partner, the company SION.
What do i have to consider if i want to have my own clones propagated by you?
For many companies it is of course very interesting to work with self-bred varieties. The basis for contract propagation is a propagation contract made with the customer. We only propagate plants selected by the customer himself. We do not propagate protected clones or active clones from competitors without a corresponding license agreement.

The sender indemnifies the laboratory against legal consequences in case of infringement of plant variety rights.
What do i have to bring to the lab to have a clone propagated?
For the contract production of customer-owned Phalaenopsis varieties we need a panicle that is as fully flowered as possible. The panicles should be cut with a sterile knife so that any viruses present on the cut surface cannot be transmitted to the plants.

For the propagation of multi-genus hybrids, the whole plant is always required, from which we then take the new shoots for propagation ourselves.
How long does it take to reproduce?
For Phalaenopsis, we need about 1.5 years until the first material can be delivered, with a desired annual demand of about 1500 plants. For other varieties, the propagation time can take longer.
How are the plants delivered?
In vitro material is delivered in our HARK Safety Cup. When delivering with our own truck in the Netherlands and Germany, the cups are delivered in reusable boxes.

For exports delivered via forwarding agents or by air freight, we use one-way packaging made of cardboard or polystyrene boxes. You can view our products on our website under "Order multiplication / Quality examples".


If you have any further questions concerning the production process or procedure, please do not hesitate to contact us!

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