Sterilizing Seed Flats

Commercial seed flats usually measure about 10 by 20 inches and are made of plastic, but the term "seed flats" can refer to any shallow container in which you plan to sow seeds. Flats that have never been used don’t require cleaning, but any that have held soil or a soilless seed-starting mix in previous seasons should be sterilized to rid them of the fungi responsible for damping off diseases. Those fungi, such as Pythium, Rhizoctonia, and Fusarium, can cause seeds to rot in the soil rather than sprouting or cause new seedlings to suddenly keel over and die.

Dishwashing gloves
Two laundry sinks
Two new garbage cans
Water
Dishwashing detergent
Bleach
Clean rag
Newspapers

Instructions

- 1
  Fill one laundry sink with hot soapy water and another with clean water. Fill one garbage can to a depth of 2 feet with a solution of 9 parts water to 1 part bleach, and another garbage can to the same level with clean water.
- 2
  Use a rag to wash the dirty flats in the sink of soapy water. Rinse them in the sink of clean water before plunging them, narrow ends up, into the garbage can full of bleach solution.
- 3
  Allow the flats to soak in the bleach solution for 10 to 30 minutes before rinsing them in the garbage can of clean water.
- 4
  Cover a flat surface with newspapers and turn the flats upside down on the papers to drain. After the bottoms of the flats are free of moisture, turn them over to allow the other side to dry.

Examples of Fast Release Fertilizers

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