Often, novice gardeners and flower growers, when buying seeds, see an unfamiliar word “stratification” on the package. What is the process, what types are there, what plant seeds need stratification?
The concept of stratification
What is stratification? The definition of stratification is as follows: this is an artificially created period of natural winter dormancy. Creation of low temperature and high humidity conditions for seeds. Under such natural conditions, the seeds are in the soil in autumn and winter.
Seeds of some plants fall into the ground in autumn and should not sprout until spring, because the cold will destroy the young shoots. The shell of such seeds is denser and harder. Only special conditions deplete the shell, the complex organic substances in the seed turn into a simple form and the seeds grow.
These special conditions include the alternation of low and high temperatures, along with high humidity.
Stratification can be carried out in natural and at home.
Natural stratification. What is "winter sowing"
Stratification of seeds in natural conditions is simple and less labor intensive. Gardeners call the process "winter sowing". For natural stratification you need:
- Sow seeds in pots or special boxes, be sure to apply drainage.
- Cover the soil with lutrasil from weeds and moisture evaporation.
- Put in a shaded place.
Gardeners with experience consider natural stratification better than artificial, domestic. Some seeds are sown in late autumn. After wintering under the snow, they will sprout themselves on warm spring days.
Home stratification
At home, seeds need to create an environment similar to natural. To do this, the seeds are mixed with coarse earth or sand, peat, moisten the soil, sift, and remove silt particles from the sand.
Experienced growers wrap seeds in damp cloth, tie with wire, and place in a container with limited water. Such rolls must be marked without fail: a label is strung on the wire, which indicates the type of seeds, the start date of stratification.
The water in the container should be at the very bottom, in no case should the fabric rolls be completely immersed in water. Air will leave the fabric and the seeds, which are in dire need of oxygen during the growing period, will die.
The method of seed stratification at home involves the need to inspect, remove damaged or rotten, moisten. This is done until the seed buds appear.roots.
After the end of the stratification period, the swollen seeds are sown in the ground and kept in a room at a temperature of 22-24 degrees.
Home stratification. What is the "refrigeration hype"?
Another simple way: stratification of seeds in the refrigerator. It is necessary to sow the seeds in moist soil, wrap in a film with a hole and put in a refrigerator or basement with a low temperature regime - up to +7 degrees. At the end of the stratification, bring the box of seeds into the room.
Important: before placing the seeds in the refrigerator or cellar, they must be kept at room temperature to swell.
Duration of stratification
The term of seed stratification depends on the type of plant. This information is usually written on the packaging. The average stratification period is one to two months. There are seeds that require stratification from one week to four months.
Which plants need stratification?
Short stratification from one to two weeks needs plants such as:
- Libyzia;
- meconopsis;
- adrianthus.
Long stratification needed for:
- most types of decorative bows;
- wormwood;
- clementines;
- corydalis;
- dryads;
- milkweed;
- geranium;
- irises.
There are plants that will germinate in the second year after stratification, to theminclude:
- helloebore;
- arum;
- adonis;
- peonies.
Stratification of tree seeds
A fairly simple example is the stratification of apple seeds. Before preparing the seeds, you need to choose the ripest and largest apple. Remove the seeds and rinse with water to wash off inhibitory substances that inhibit the growth process. Next, soak the seeds in water for 3 days.
On the third day, add a growth stimulator to the water, for example, "Epin".
Preparing a substrate of sand, vermiculite and activated carbon. Charcoal is essential to prevent mold. We moisten and mix the prepared soil with swollen seeds. Pour the soil with seeds into a container and put in the refrigerator. You can use a flower pot or a small box. The container should have large drainage holes to remove excess moisture.
In an apple tree, the process of stratification takes a considerable time - about 90 days. All this time it is necessary to check the soil, if necessary, moisten it from the sprayer.
If you start the stratification of apple seeds in early February, the seeds will be ready for sowing in May.
Flower seed stratification
Many flowers have a low germination rate, which makes them impossible to grow without a stratification process. Such flowers include peonies, buttercups, irises, lavender, aconites, anemones.
With a small number of seeds, stratification can be carried out according to simplified options:
- Sow seeds in cups, place them inplastic bags through the holes and put in the bottom of the refrigerator.
- Cut into 15x50 cm fabric flaps, evenly distribute the seeds over the canvas. Bend the edges of the canvas, securing the ends. Place the rolls in a bowl, pour a little water on the bottom and place in the lower section of the refrigerator.
The stratification process is simple, after trying it for the first time, you can grow a wide variety of flowers.
On what successful stratification depends
Main factors that influence the success of stratification:
- Seed quality. Seeds must be collected recently. Otherwise, some seeds will completely lose their viability and disappear.
- Decrease and increase in temperature should be smooth.
- Compliance with the time frame of the process. If stratification is not completed, seed germination will be limited.
- Determining the duration of periods. For some plants, the cold period should be longer than the warm period and vice versa.
- Compliance with the temperature regime, which varies from 0 to -5 degrees. This type of plant, like ranunculus, must be frozen at sub-zero temperatures.
- Determine the need for a scarification process. The seeds of some plants and trees have a very thick shell, they are shaken with sand or rubbed with sandpaper before sowing.
![term of seed stratification [1]](https://i.designhouseroom.com/images/013/image-38504-6-j.webp "term of seed stratification [1]")
Why is seed stratification necessary? What nature did not provide, since a person had a need to intervene innatural growth process? The ability to control the time and course of seed germination, obtaining he althy and efficient seedlings will make a true breeder out of a simple gardener. Stratification allows you to grow varieties of vegetables that are resistant to winter storage. For example, artificial stratification of carrots allows you to store grown root crops in winter.
In addition, there are seeds of rare plants, which count for a few. The process of stratification just allows to save their number.
