* The seed of these plants (see below) only germinates with a cold stratification. This process         takes weeks to months (see below). It is worth remembering that up to 70% may not germinate with        some species. If the seed does not undergo stratification, it may take years to grow       germinated.

* The seed must be between 3-double moist kitchen paper with moist cotton wool on the inside      be done and covered with the same. Hydrogen peroxide must be added to the moisture      be used to prevent mold growth.

* Then in a plastic bag at the bottom of the refrigerator at a temperature of 5 - 6 degrees            (not near fruit and vegetables, due to chemical influence).

* While the process lasts, the kitchen paper must be kept moist (check), and       be aired twice a week.

* When the seed germinates over time, it can be planted in seed trays or pots,        where there is a hole at the bottom, so that the water can escape (moisten moderately, but do         keep slightly moist). Use sterile seed soil.

* The germination of the seeds must go down (root), and the temperature must then

   be 18 - 21 degrees.

* First two germ leaves appear above the ground, and only then the other leaves. After this one     During the first leaves, the tips are cut away to give the roots more energy.

* Then they can be transplanted into larger pots. The plants must then also            get nutrition (never too much).

* The plants often do not flower the first year.

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Species requiring stratification:

* Acer (maple) , 6 months

* Aesculus (horse chestnut) , 3-4 months

* Aconitum (monks hood), 3 weeks

* Amelanchier (currant tree), 6 months

* Antirrhinum majus (snapdragon), 4-6 weeks

* Aquilegia (columbine), 2-8 weeks

* Carpinus betulus (hornbeam), 6 months

* Castanea (chestnut), 3-4 months

* Clematis, 3 months 

* Consolida (annual delphinium), 6 weeks

* Crataegus (hawthorn), 1.5 years

* Dianthus (carnation) , 4-8 weeks

* Dicentra spectabilis (broken heart), 6 weeks

* Dracocephalum (dragon head), 4-6 weeks

* Echinacea (coneflower) , 3-6 weeks

* Eryngium (cross thistle), 6 weeks

* Euonymus (cardinal's hat), 1 year

* Fagus (beech) , 3-4 months

* Fraxinus (ash)

* Gentiana, (gentian), 2-4 weeks

* Geranium sanguineum (cranes' bill), 1-2 months

* Heliopsis helianthoides, 4 weeks 

* Ilex aquifolium (holly) , 1 year

* Juglans regia (walnut / walnut), 3-4 months 

* Lathyrus odorata (green pea / sweet pea), 2-3 weeks

* Lavandula (lavender) , 4 weeks

* Liatris scariosa, 6 weeks

* Lobelia cardinalis (scarlet lobelia), 10 days

* Mimilus (mask flower), 3 weeks 

* Oenothera macrocarpa (evening primrose), 2 weeks 

* Paeonia (peony), 2 months 

* Penstemon, 4-8 weeks 

* Polemonium boreale (Jacobs Ladder), 2 months 

* Primula marginata (primrose), 2 weeks 

* Quercus (oak) , 3-4 months

* Rosa (rose) , 4 months

* Salvia, 1 week

* Sanguisorba canadensis (blood root), 6 weeks

* Sorbus (mealberry and mountain ash) , 3-4 months

* Yew (venom tree), 1.5 years

* Veronica (speedwell), 2 months

* Viola (violin), 4 weeks

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Freezing period for the following seeds:

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* Delphinium elatum (larkspur), 4-6 weeks 

* Euphorbia griffithii (spurge), 2 weeks 

* Helleborus niger (Christmas rose), 2 weeks

* Hemerocallis (daylily), 2 weeks 

* Molucella laevis (Irish bluebells), 5 days 

* Phlox, 2 weeks

* Rudbeckia hirta (rough rudbeckia), 1 week + 1 week cooling

* Trollius europaeus (bullet flower), 2 weeks 

* Yucca filamentosa (palm lily), 3-4 weeks