Starting Transplants for the Home Garden
Winter is in full swing and home grown produce is probably not the first thing that comes to mind. But it should be! It’s time again to start thinking about spring vegetable gardening. While a number of crops can be started by direct seeding in the soil, success rates are higher when plants are started indoors or in a covered structure. In order to be successful, it’s important that you follow some simple steps.
Seedless watermelons planted in a 128-cell flat. Photo Credit: Gene McAvoy, University of Florida/IFAS Extension – Hendry County
- Transplant Trays/Flats – Trays are made from different materials such as plastic, polystyrene, and compostable materials. Different cell sizes are also available. Generally, smaller cells are used for smaller seeds and larger cells are used for larger seeds. It’s important to think of the life cycle of the crop. For example, lettuce and other leafy greens have much shorter life cycles compared to tomatoes. Because of this, they have smaller root systems at transplant time and may not develop a good rootball in a large cell. Therefore, lettuce would perform better in a smaller cell.
- Media – It’s important that you choose a germination mix instead of a potting mix. Definitely don’t use garden soil! Germination mixes are typically a combination of finely ground peat, perlite, and other soiless substrates.
- Seed – Purchase seed from a reputable source with a germination guarantee. If you save seeds for future gardening, then store them in a cool, dry place. Seed can be stored in the refrigerator. However, do expect the germination rate of stored seeds to diminish over time. Coated seed is recommended for smaller seeds to make seeding easier and more efficient. Seeds should be planted in media at a depth of approximately 3 times the diameter of the seed. Check the seed package for additional planting recommendations. For more germination and storage information please see this publication from the University of Nebraska.
- Fertilizer – Too much fertilizer can result in leggy and possibly burned plants. A 20-10-10 (or similar ratio N-P-K) water-soluble product is generally used in commercial production. Rates are dependent on crop, sunlight, and temperature. The media should be kept moist, but not continually wet.
Well-grown kale transplants ready for field planting. Photo Credit: Gene McAvoy, University of Florida/IFAS Extension – Hendry County
Seeds can take up to 14 days to germinate depending on species and conditions. Most transplants are ready for the garden by 6 to 8 weeks. To improve success rate and accelerate production time, most farmers harden off their transplants before planting. Hardening off is the process of stressing the transplants for about a week. Generally, transplant trays are taken out of the greenhouse (or other transplant area such as a window sill) and set outside. Watering frequency is reduced and fertilization is halted. It’s important that the plants aren’t completely neglected, but just stressed enough to prepare them for the elements. A good place to put the trays is under a tree in partial shade. After this hardening off period, the transplants are ready for your garden. Hopefully these tips will make you a more successful gardener!
