Hosta can be propagated in different ways, but one of the most interesting is the generative method. As a result, you can get very exciting specimens that can become new varieties.
To propagate a hosta from seed, collect the seeds when they are mature. Put the seeds in a box and move it into a cold room for the winter. Sow the seeds in sterile soil in early spring and keep the air and soil moist. A few weeks later the seedlings will sprout.
You should be aware that hosta varietal characteristics are not transmitted by seed propagation. In other words, the new plants will not look like the one from which the seeds were taken. However, some hostas from the seed can be much more beautiful and unusual than the mother plant.
How to collect hosta seeds?
To harvest hosta seeds, you have to wait until they are mature. On average, it takes 30-40 days after pollination for the seeds to ripen.
The obvious sign that the seeds are ready to be harvested is a brown and dry seed pod. If you wait a little longer, the pod will open and the seeds will fall out.
You need to cut off the seed pods when they are dry but not yet open. Then collect everything in a tray and peel the seeds from the pods.
Then dry the seeds in a dark and dry place for 1-2 days. After that, place them in a paper bag.
Some hostas bloom rather late and their seeds can take over two months to set. Usually, the seed pods of such hostas stay green until the first frosts.
In this case, you will need to harvest the seeds sometime in September or October. Cut off the green seed pods where they attach to the stem.
Then gently tear open the seed pods and pull out the seeds. They will be moist, so they will need to dry out for about a week, but don’t place them near a heater. The seeds should be left to dry at room temperature and then placed in a paper bag or envelope.
How long are hosta seeds viable?
Hosta seeds remain viable for about a year. This is just enough time to get everything ready and sow the seeds.
The best time to sow hosta seeds is in spring. The weather should be warm. In addition, the whole season is ahead and the seedlings have time to grow and gain strength for the winter.
However, you should be aware that not all seeds in the seed pod are viable. Some of them may be very weak and will not germinate.
Moreover, some hostas produce completely sterile seeds that will never germinate. This means that you have to be prepared for the fact that if you sow the seeds, they may not come out at all.
Do hosta seeds need cold stratification?
Stratification is not necessary for hosta seeds. Seeds are capable of germinating without pre-cooling.
However, stratification increases the number of seeds that will germinate. This is because stratification mimics natural conditions. If the seeds are in the cold, followed by warming, it means that spring has arrived. As a result, a slightly higher percentage of seeds will come out.
To stratify hosta seeds you can go two ways. The first is to put the seeds in the refrigerator a few weeks before sowing. When spring arrives, take them out and sow them right away.
The second way is to put the seeds in a paper bag and put the bag in a cold garage. Also, any other unheated room will do. This will result in a milder stratification but will be enough to increase germination.
How do you prepare hosta seeds for planting?
To prepare hosta seeds for planting, treat them with fungicide and soak them in water. These steps are not necessary, but if you do, you will get better results.
The first thing to do is to treat the seeds with fungicide. To do this, buy a special seed dressing product or use a multi-purpose fungicide.
Dilute the product in water as directed on the label and pour the hosta seeds into the solution. Keep the seeds in the solution for about an hour so that they are well dressed.
This will ensure that all pathogens are killed. As a result, the number of seedlings will be higher and the quality will be better. If you use a biological dressing, the seedling will be protected throughout the first year of life.
Next, extract the seeds from the solution and place them in clean water. Let them soak in the water for a few hours. This will wash away the excess fungicide and give the seeds the moisture to start the germination process.
After that, pull the seeds out of the water. That is basically it, the seeds are ready to sow.
How to plant hosta seeds?
Use trays or individual pots to plant hosta seeds. Make sure the container has drainage holes for draining excess water.
Use sterile seedling soil as a substrate, which can be purchased from your local home improvement center. The soil should be of good quality and free of pathogens. If the soil is of poor quality, the seedlings may die in the first few weeks after sprouting.
Fill the container with soil to about 1 inch below the edge. If you are using individual pots put one seed in each pot. Place the seeds flat side down on the ground.
If you are planting in a tray spread the seeds evenly over the surface. The seeds should be about half an inch apart.
Sprinkle half an inch of soil on top of the seeds. Next, water the soil well. High humidity will encourage the seeds to germinate.
Place the container in full shade. It should remain in this location all year long.
Place a transparent dome on top of the container to keep the air humid. When the seeds have sprouted, remove the dome. Or you can put the seed container in a greenhouse if possible.
How long does it take to grow a hosta from seed?
It takes about 2-3 weeks for hosta seeds to germinate. At this stage, up to two leaves will appear on each seedling.
Depending on the temperature, the germination time will vary. If it is warm enough outside, the seeds will germinate quickly.
In any case, you need to constantly monitor the moisture of the soil. It should always be slightly moist.
Also, the timing of germination and the rate of further development is influenced by the mother plant. If the mother hosta was a vigorous and large variety, the seedlings will also be strong and full of energy.
It is usually not necessary to transplant seedlings in the first year. At this age, the hosta will remain quite small and form a root system.
However, if the pots in which the seeds were sown are small, the seedlings may outgrow them. In this case, transplant them into larger pots but do not damage the roots.
Carefully remove the hosta from the old pot and place it in a larger pot. Transplant no sooner than a few months after germination, but no later than late summer.
During the first year of life, the seedlings should be in complete shade, so they can’t be exposed to direct sunlight. Only when they are a year old can they be transplanted to the garden.
Can you plant hosta seeds in the fall?
You can plant hosta seeds in the fall. This way you can stratify the seeds in a natural way. In nature, seeds fall to the ground in the autumn and stay under the snow all winter. They germinate in the spring with the arrival of warmth.
If you sow hosta seeds in the fall, you will mimic the natural propagation of hostas. However, you need to be aware that the germination rate will be lower than if you sow the seeds in containers with sterile soil in the spring.
In the fall, you only need to plant the seeds outdoors. Avoid sowing seeds indoors at this time. Seeds need to hibernate over the winter.
In general, fall sowing of hosta seeds is rarely practiced because of the difficulty and low efficiency.
Can you plant hosta seeds directly in the ground?
You can plant hosta seeds directly into the soil. This will make the sowing process much easier. All you have to do is loosen the soil a little and spread the seeds out evenly.
If you keep the soil slightly moist, the seedlings will sprout after a while.
However, you have to be aware that a significant number of seeds will not germinate. This will happen because the soil in the garden is dirty and saturated with pathogens. As a result, some seeds will die.
The second thing that will happen is mold will destroy some of the young seedlings. All of these losses are normal and are called natural selection.
To make things a little better, fill 2 inches of sterile store-bought soil on top of the garden soil. The garden soil should be loosened a little beforehand.
Then sow the seeds on top of the sterile soil. Next, cover the seeds with about a half-inch layer of this soil. After that, water the seeds well.
The best time to sow the seeds directly into the ground is the first half of spring.
Growing hostas from seed indoors
Growing hostas from seed indoors are more challenging than outdoors. You have to create the right conditions to succeed.
The first thing is to get a humidity dome where you can place your pots. You need this to provide enough humidity because room air is too dry for hostas.
The second is an LED light with intensity control. You can’t just put the pots on a window sill because the sun will burn the seedlings. You have to use artificial light to germinate the seeds.
And lastly, you need a proper place to put everything. This can be a table or a rack. The temperature in the room where the seedlings will germinate should be around 68°F (20°C).
Beyond that, the process of germinating seeds indoors is the same as germinating them outdoors. Around May-July, when it is warm, take the seedlings outside in the full shade.