Nasturtium does not only belong in cottage gardens . It is both ornamental and useful plant and can repel pests. For the earliest possible flowering, the nasturtium can also be easily grown indoors with our instructions.
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The required seeds can be purchased commercially or harvested from existing plants. They should be fully mature by the time of harvest. Immature green seeds would probably go moldy during storage and spoil the whole seed.
- Nasturtium seeds comparatively large
- sit in seed coats
- mature seeds are easily detached from brown seed coats
- simply open the seed coats to harvest
- extract seeds
- or wait for them to fall to the ground by themselves
- then just collect it
- only harvest in dry weather
Choose the right time
Nasturtiums can be grown on a warm windowsill from the beginning of February. However, due to the lower light output in February, it is advisable to wait until mid-March or early April. As an alternative to the window sill, a heatable greenhouse is also suitable for early cultivation .
It is often recommended to soak the seeds in lukewarm water before sowing. In most cases, however, you can do without it. However, one should bear in mind that the seeds of the nasturtium are warm and dark germs . Now it can be sown.
- fill the culture vessel with substrate to prefer
- Press the soil lightly
- Spread seeds on it
- Two to three seeds per pot
- then cover an inch or two with soil
- press lightly and moisten
- Cover pots with cling film
- put in a bright and warm place
Standard growing pots are just as suitable as growing containers, as are small flower pots with a diameter of six to ten centimeters and greenhouses . It is important that excess irrigation water can drain off at any time. Pots that have already been used and that you want to use again should be thoroughly cleaned beforehand to kill any germs and pathogens.
Create optimal germination conditions
For the germination of the nasturtium, heat and constant moisture are of particular importance. If necessary, you can support germination by pre-soaking the seeds.
- Temperatures to prefer ideally between 18 and 21 degrees
- adequate heat and humidity is essential
- Covering with translucent film recommended
- dry air prevents germination during pre-breeding
- dry seeds have limited metabolism
- Keep the soil constantly moist throughout the germination period
- Use nebulizer to moisten
- prevents the seeds from being washed away
- Light is not required, nasturtium is dark germ
- under optimal conditions germination within 10-14 days
- first seedlings often after a week
Prick out seedlings
So that the seedlings of the nasturtium can develop into strong young plants, they should be isolated after cultivation. The right time has come when the roots are already growing out of the bottom of the pot, the small plants are beginning to fall over due to their size, or the root ball dries out too quickly.
- have a separate pot ready for each plant
- with a diameter of 13-15 cm
- Fill about halfway with soil
- commercial vegetable or herbal soil is well suited
- both contain all the necessary nutrients
- put one plant in each pot
- just as deep as in the culture vessel
- Fill the pot up to just below the rim with soil
- then press down the soil well
- Roots need good ground contact
- finally water well
- Keep the substrate constantly slightly moist
Harden young plants
Before the preferred plants can be planted out, they should be hardened off. This way they can slowly get used to the new conditions. When the weather is mild, you put them outside during the day and bring them back inside at night. It is important to ensure that they are not exposed to the blazing sun to avoid sunburn.
Plant out in the bed
As soon as no more night frosts are to be expected, the nasturtium can be planted out in its final location in the garden.
- usually from mid-May after the ice saints
- Plants like it sunny
- also do well in semi-shade
- ideally in clay soil
- should also be sandy and calcareous
- the poorer the soil, the more flowers
frequently asked Questions
If there is no germination, this can have several causes. For example, the seeds may have been too old, stored incorrectly, or sown too deep. The substrate may also have been unsuitable, too cold or too dry.
In rather mild locations, these plants also self-seed and appear anew every year. However, there is also the possibility of overwintering perennial varieties in particular with appropriate protection. Annuals must be resown every year.
Many are of the opinion that pre-soaking will speed up germination or get it started in the first place. There is no question that the seeds need moisture to germinate, because they themselves contain little water. This doesn’t necessarily mean that they need to be soaked, a sufficiently moist substrate serves the same purpose. Cress seeds in particular swell up in water and burst, which in turn can lead to rot. The positive effect remains.