Starting your own transplants can save you money, allow use of varieties that are hard to find, or just let you get a head start on your garden. You will be most successful if you:

• have a location with bright light,
• use sterilized planting medium and containers
• do not start the seedlings too soon

Most plants germinate at 75 to 80 degrees Fahrenheit. However, some plants germinate better at 50 to 65 degrees. These include broccoli, parsley, cauliflower and celery. In general, seeds should not be started until 4 to 6 weeks before you plan to put them into the garden. There are exceptions such as parsley at 10. Some plants take less time, such as melons and squash (3 -4 weeks). Starting seedlings too soon results in weak, leggy plants. If they survive they will have delayed growth once they are planted into the garden.

A south-facing window is helpful once the seeds have germinated. In Minnesota additional light is usually required for good transplants. Fluorescent lights provide a broad spectrum of light. Lights should be placed 6 inches above the seedlings and raised as the seedlings grow taller. As soon as the seedlings are 3 inches tall, lightly brush them ten strokes each day with your hand to keep them sturdy and strong. Most plants grow best at temperatures between 60 and 80 degrees.

Seven to ten days before planting out in the garden, the transplants need to be hardened off. Exposing the plants to increasing periods of outdoor conditions does this. Start by placing the plants in a sunny, somewhat sheltered area for an hour or two the first day. Gradually increase the length of time the plants remain outside.

Remember to check plants frequently to see if they need water. Do not allow the transplants to dry to the point of wilting. By the tenth day, the plants should be adequately hardened off. Plant directly into the garden or keep them in a cold frame if frost is expected.

For more information visit the Yard and Garden Line.

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