Hill Gardens of Maine - Seedlings...Transplanting & Growing-on

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Transplanting & Growing-On Seedlings
by Fred Davis, MG, Hill Gardens of Maine (To view other articles, click: Archives)

Welcome through Fred's Garden Gate! Last time we focused on the disease of stressed seedlings known as damp-off. (To view the article, click Damp-off. Use the back-button to return here.) A combination of care, attention to cultural requirements – ample light and ventilation, avoidance of excess moisture and a clean (sanitary) seedling environment – and a little good fortune, should result in strong, healthy, stocky seedlings ready and anxious to be moved into larger containers. That next step in the process is referred to as transplanting.

A seedling is ready to transplant into its intermediate home as soon as its first true leaves have developed. A true leaf is normally one that looks like that of its parents – except in miniature. Soil for transplanting is usually higher in organic matter and nutrition than that used in the seed tray.

I prefer to move seedlings up to their own individual containers rather than into a communal flat. That way they're only disrupted once and seem to mature quicker. I also like to transplant on a cool, cloudy day.

Soil should be 1/4-inch screened, rich with compost and adjusted to the proper pH (usually 6.5 to 7.0). You can mix your own soil and store indoors until needed, or purchase ready-mixed soil in garden stores. Some store-bought mixes may be a bit ‘heavy’ and, in that case should be lightened with a little extra peatmoss and clean sand or perlite. An ideal – commercial – mix is either Johnny’s Soilless Mix No. 512 (available at the retail store in Albion), or Pro-Mix BX that you can purchase at most garden centers and farm-‘n-gardens in the area. Pro-Mix contains a small ‘shot’ of non-organic fertilizer so, if you are a strict or certified organic gardener, consider the alternative. Both of these are clean, weed-seed-free, may be considered relatively ‘sterile’ and are well suited to growing-on precious seedlings.

Loosely fill pots and trays with moistened soil mix and lightly firm the surface with something clean. Using a pencil or dibble, poke a hole wide and deep enough to accommodate the roots. Remember: sanitation!

Seedlings should be handled only by their leaves, never by their very fragile stems. I use a plastic dibble about the size of a new, sharpened pencil, to gently pry out young seedlings while I lightly lift by their leaves. Do them one at a time so delicate roots don't have a chance to dry out. Insert each seedling's roots to about the same depth and lightly press the soil around them with thumb and forefinger. Taller, leggier seedlings may be transplanted a little deeper to place the point where leaves emerge closer to the soil surface. Water immediately, from the bottom, or from the top using a very gentle spray. Once again, Johnny’s offers a perfect watering wand, well suited to moistening newly transplanted plant babies. Be sure to lift little leaves and faces out of the mud.

Newly transplanted seedlings should be given good light but no direct sun until they show signs of active growth. Begin liquid feeding immediately after transplanting using a balanced natural nutrient like Sea-Plus liquid seaweed/fish fertilizer (3-2-2) or SeaCom-PGR seaweed concentrate (available at www.johnnyseeds.com). Peters 15-16-17 can also be used if strict organic growing is not an issue. Feed at weekly intervals until the weather allows your now-vigorously-growing plants to be moved outdoors. If they seem to be growing too fast, back the feeding off and try to provide more light. The trick to keeping them from becoming tall, weak and spindly is to balance growth - especially height - against the time for setting-out in the garden.

As the time to begin soil preparation and outdoor planting grows nearer, consider some general gardening principles:

Avoid tilling or working soil that is still too wet.
If you must use a rototiller to prepare your garden, once through is enough. Resist the temptation to repeatedly pulverize soil with machines (a great many old-time gardening professionals call that common gardening error ‘recreational rototilling’ – literally bludgeoning the life and structure out of soil).
Remember that soil temperature is also an important factor. Transplants installed into cold, wet soil will just sit there, doing virtually nothing until soil warmth increases – and may actually rot and die while waiting for that to happen.
As conservation of resources continues to be a critical environmental issue for all gardeners, the use of plastic mulch, cloches and affordable slow-drip irrigation systems will insure consistent moisture, non-chemical weed control and earlier warming of the soil – all factors that will dramatically enhance both gardening experience and harvest results.

Consider season-extenders like row-covers and low-temperature-defying devices like ‘Wall-O-Water’ to move up planting dates as many as two or three weeks.

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