Petunia Rooting Materials

The most convenient and cleanest media in which to sow fine Petunia seed is vermiculite. It comes sterile and if the pot or flat is sterilized, the danger of loss of seedlings from damping-off will be reduced to a minimum.

If seed is started in vermiculite which supplies no food, it is necessary to fertilize the plants, lest they starve. As soon as seedlings can be seen, they must be watered with a solution of a complete fertilizer. Soluble forms are better as they will not burn the foliage when applied in a weak solution according to directions.

Hyponex, Miracle gro, Peters and many other liquid foods are all good. Other brands, if they’re recommended for this use, are probably safe. To avoid all risk, fertilize with half the recommended strength, but then do it more often – perhaps three times a week. This type of watering is always done from the top and then rinsed off each time.

If soil is used, sterilize it as well as the flat or pot. Put it in the oven for an hour at 180 degrees. When sowing, the soil should be moistened more than usual in order to compensate for water lost in sterilizing.

Some gardeners prefer a mixture of soil and vermiculite. The soil must still be sterilized but fertilizing is, of course, not necessary. With this method, a half-inch layer of vermiculite is placed over the sterilized soil and the seed is sown on it. When seeds germinate, the little roots penetrate to the soil below.

Sowing Seed

If vermiculite and a self-watering pot are used, spread a sterilized wick over the bottom of the pot and fill it with vermiculite to within a half inch of the top. Firm this slightly with a round, smooth object and sow the seed on the surface, spreading it evenly and thinly. If the vermiculite is kept moist, the fine seed will sift down into it. Unless the vermiculite is allowed to dry out, the seed will not become exposed and, therefore, will not need a protective cover.

After sowing, water the vermiculite with a sprinkler thoroughly in order to establish capillarity and insure rise of water up through the vermiculite. Then, place the pot or flat on a pan or bowl of water and put the wick in the water. The level of the water should be kept to above the end of the wick at all times.

As soon as seedlings are visible, place the pot in a sunny window of a cool room. About 60 degrees at night and 70 degrees during the day is ideal if there’s plenty of sun. If the room is dark or gets direct sun only during part of the day, a cooler temperature is necessary. Don’t worry if it should get as low as 40 degrees. The petunias will love it and become stronger and sturdier.

If soil is used in the self-watering pot, the soil is leveled and firmed loosely with a short piece of wood before seed sowing. Then, the pot is placed in a pan full of water. Every two or three days, water is added to this when needed, although it is not desirable to keep water in the pan at all times. The surface of the soil should always look moist. Too much moisture, however, impairs germination.

by C Weddle

Related Articles Of Interest:

• Germinating Tuberous Begonias
• Tips and Guidelines to Growing and Propagating Seeds
• Easy Grow Penstemon
• Grow Your Own Perennials On A Limited Budget