Setting Out, continued…

Hardening Off

Transplants that have been raised indoors are soft, and must get used to sun, wind and rain. It is best to let them “harden off” gradually for several days before planting in the garden.

Move the trays of transplants outdoors to a sheltered, shady place out of the wind. Keep them well-watered. (If they wilt anyway, bring them back inside until they perk up again.) Bring back indoors each evening.

After two days, leaves and stems should be stronger. Move transplants to a half-sun location for 2 more days. When they are tough enough to go through the day without wilting, it’s time to plant them in the garden or container.

Setting Out

Plant Condition

It’s best to set your transplants out before they begin to bloom, since a young garden plant needs its energy to grow roots, not flowers. If your transplants set flower buds or bloom before planting out time, disbud them or cut off the blooms.

Plants are definitely ready for the garden when roots grow through the bottoms of their containers, but you can hold most types up to 4 more weeks before planting, if you must wait for ideal planting weather. While each type is different, a good rule of thumb is to set plants out when 2 to 4 inches tall. Plants for container gardens should be set out at this same stage.

Care After Transplanting, continued…

Pinching

If plants get too tall before planting time, pinch them back. Leave plenty of foliage and some branches so growth can continue, but pinch off just above a lower leaf or branch (see diagram). A small pair of pruning shears does a better job than fingers.

 

Care After Transplanting, continued…

Watering and Feeding

After seedlings are established, with healthy roots spreading through the soil, they will need a drier medium and less frequent, but more concentrated feedings. Let the surface of the soil become dry to the touch between waterings (lower layers should still never dry out). Feed once a week using a water soluble fertilizer.

Care After Transplanting, continued…

Growing On

Growing on to garden size plants may take only a week or it may take several months, depending on species. Your seed packet instructions and the Park Seed Catalog’s Cultural Index give detailed information about each type of plant.

Care After Transplanting

Seedlings may droop or wilt somewhat right after transplanting, if some roots were broken or disturbed. To speed recovery, keep them quite moist and out of the sun for 2 days, then give then filtered sun or half-day sun for 2 days, after which they should be ready for bright light.

Growing Seedlings, continued…

Transplanting from Park’s Bio-Domes, Park-Starts^®, One-Steps or Cell Trays

If you have sown seed into one of these kits, you can skip most of the steps for transplanting. As  the seedlings grow larger and begin to touch, either space them further apart, if possible, or plant them into approiate sized pots to avoid transplant shock. Or you may set them directly in the garden if the weather is right.

Growing Seedlings, continued…

Feeding

You can begin feeding your seedlings even before they emerge! When you water your seedling flats, simply use a weak fertilizer solution instead of plain water. We recommend 1/4 teaspoon of Park-Start® Fertilizer per gallon of water at room temperature. Your seedlings should be kept looking healthy, with a strong green color. Yellowish green may mean more nitrogen is needed, so fertilize a little more (increase gradually). A “burned” look may indicate too much fertilizer is present. Water from the top in this case, using plain water, until it runs out of the bottom, thus removing excess fertilizer salts. Then reduce feeding rates.

Growing Seedlings, Continued…

Moisture

Check the moisture of your growing medium in the flat. Air movement, bright light and warmth, while needed, also cause fast drying. Keep the medium less moist than while seeds were actually germinating, but still don’t let its surface dry completely, until your seedlings grow a little bigger. You may need to cut watering back to every second or third day, rather than daily.

Watch seedling stems carefully.  If some of them fall down, the base turning brown and collapsing though the leaves still look good, this may indicate “damping-off”. This is a disease that is encouraged by too-wet soil and poor ventilation. Reduce watering and increase ventilation. A fungicidal drench may also help.

Seedlings whose leaves droop or shrivel, or whose stems, though not discolored, bend over along their entire length, are probably too dry, so soak the flat thoroughly.

Growing Seedlings

Location

Seedlings of different species require different conditions for best growth. In some species, the seedling prefers a temperature different from the germination temperature. Read your seed packet, and pick out ahead of time favorable places to move your seedling flat after emergence.

After emerging, your seedlings should be moved into a desirable location; your seed packet will indicate desired light and temperature. All seedlings need light to develop into strong, healthy plants. In dim light they will grow too tall, with weak, spindly stems. Fluorescent grow-lamps, greenhouses, or cold frames are a big help, but protected beds or sunny windowsills work well also. Avoid cold drafts for warmth-loving kinds.

Seedlings also need air circulation for good health, so avoid locations that are too closed-in. Remove the clear plastic cover from the flat as soon as emergence occurs.