While petunias are often found in the wild in their homeland of South America, these nightshade plants cannot go wild in the open in this country due to their sensitivity to frost. Since petunias can be easily grown from seed and are cheap to purchase, they are often only cultivated as an annual, despite the fundamental possibility of overwintering.

Petunias should only be planted outside after the ice saints

What are the main characteristics of these plants?

Petunias grow herbaceously and usually have sticky fibers with plant hairs called trichomes on their shoots. With appropriate fertilization and care in the balcony box, some varieties can develop into a hanging carpet of flowers up to one meter long. Since the individual blossoms of the petunia constantly wither and grow again during the flowering period, the sticky remains of the blossom should be plucked off regularly for reasons of appearance and disease prevention.

Which location do petunias prefer?

If necessary, petunias can also be planted in partial shade, but they only develop their full bloom in full sun. Since petunias do not tolerate waterlogging, they should be planted in a substrate that is as permeable as possible and has a high nutrient content. However, a very sunny location in summer also makes it necessary to water it almost every day.

When can petunias be sown and planted out?

The seeds of the petunias can be grown in a bright and warm place on the windowsill from January. Since germination is favored by high humidity, you should use a greenhouse if possible or use a plastic sheet to cover the seed pots (16.68€). After a few weeks, the young plants can be carefully separated into individual seed pots. However, they are only allowed to go outside after the last night frosts and the ice saints, as petunias are very sensitive to frost.

How to propagate petunias?

Petunias can be grown from seeds you bought or collected yourself. If you plan to harvest seeds from your petunias yourself for next season, do not remove wilted flowers before the seed pods are mature. In the summertime you can also simply cut off an approximately 20 centimeter long side shoot from the petunia and, after removing all the flowers and part of the leaves, place it in a glass of lime-free water. As soon as roots have formed about two to three weeks later, this offshoot can be planted in the ground.

How long does the petunia bloom?

Depending on the time of cultivation and location, petunias bloom from around June until the first frost. If you want to start the new season as vigorously as possible with hibernated specimens, you must regularly remove any blossoms that appear in the winter quarters.

Which plant substrate do petunias need?

Petunias usually thrive in ordinary potting soil, but the following factors are important:

  • loose, crumbly substrate (easy to root through)
  • as permeable as possible (petunias do not tolerate waterlogging)
  • very rich in nutrients

Special petunia soil is usually already mixed with a long-term fertilizer to cover the high nutrient requirements. Commercial potting soil can also be poured with an iron fertilizer to prevent chlorosis.

tips

Since petunias suffer from summer rainy periods and can then only develop their flowers insufficiently, they should be positioned under a roof overhang if possible. However, you should pay even more attention to sufficient and regular watering for covered petunia stocks.

Category:

Indoor plants