Your goal when growing seedlings is to make them as strong and
sturdy as possible, and do it as quickly as possible.
Excellent instructions for growing healthy seedlings are contained
in Let’s Grow Tomatoes pages 51-53 and Grow-Bed Gardening pages 86 – 92, and Grow-Bed Gardening has many pictures illustrating the
Regrettably, both these books are temporarily not available in hard
copy, as we have sold out the most recent editions. We hope to soon
have them both available for download on the website. Both books
are contained in the Gardening Library CD, which I highly recommend.
Meanwhile, here is what Let’s Grow Tomatoes says about pruning
leaves to keep the plant stems from becoming spindly, with
parenthetical comments added by me:
“When the leaves begin to overlap the leaves of other plants, the
experienced grower who insists on thick-stem plants prunes off the
leaves which overlap (carefully pinch them off with your
finger and thumb). Pruning off the leaves increases the light
around the plant stems, and does not stop the growing tip from
growing (NEVER take off the growing tip, and always leave 2 or 3
leaves! You can even take off a partial leaf.). Pruning off the
leaves temporarily stops the upward growth of the plants, and
encourages the stems to thicken, which is what the grower desires.
“During this temporary period of reduced growth in the plant, the
grower has two choices:
1. to wait 7 to 10 days for new leaves to grow and overlap again and
pinch as before,
2. or, he can shift the plants into larger pots or gallon-size
“In the first choice the leaves must be pruned off again at the
proper time to keep the plants from getting spindly (because the
stems quickly become tall, thin, and weak as the plant stretches
looking for light), using the same procedure as explained earlier.
“In the second choice, shifting the plants into larger containers
provides more space between plants, delays pruning until a later
date, and encourages the stems to thicken – due to increased light
and circulation around the stems.
“If, therefore, space is available in the seedhouse to accommodate
larger containers, it is recommended that the plants be shifted from
the smaller pots into 4-inch pots or gallon containers before they
are pruned the second time.”
After 2 prunings, it is recommended that the pots be physically
separated to provide light to each plant, rather than continuing to