The seedlings are sown, by population, at a shallow depth in a seedbed. Then they are maintained at a controled temperature and humidity, until the seeds sprout and the plants have produced at least 4 leaves. Following this, the temperature is lowered, to harden the little plants.
The small plants are transplanted into individual pots, selected by population. After the plants have died, one tuber is harvested per pot; the glasshouse clone.
The seedlings are selected every following year. The art of the process requires a lot to be thrown away.
For screening of the seedlings, we have trial fields all over the world. From the glasshouse generation (G0) no seedlings are selected. Stage 1,2 and 3 are planted in one field, stage 4 in five fields in the Netherlands and from stage 5 onwards we also screen on trial fields outside the Netherlands.
The seedlings are tested annually according to a testing schedule. After evaluation, a selected seedling is taken forward to the next year.
1. When decided what seedlings and varieties are planted on local trial fields, demo fields and on trial fields of foreign clients, the necessary tubers are being prepared.
2. The tubers are planted on the trial fields, at equal distances and of course, marked so we know what it is. The seedlings are grouped together by year.
3. During the growing season, the potatoes are frequently rated on various characteristics. For example, emergence (early, late), foliage development, berries, flower colour and degree of blossom, earliness, etc.
4. Plants with viruses are removed and noted.
5. The harvest can be done by hand or machine, a first analysis is made while still in the field, where we look at tuber characteristics like eye depth, skin colour, stolon length and the uniformity of shape.
6. Subsequently, the tubers that are deemed suitable are taken to the warehouse.
In the warehouse and the trial lab, various aspect are rated;
Based on all the information from the trial field and the rating we decide;
That way, the selection thins year on year and eventually, only the best seedlings remain, which we register and market.