Q&A with Jorge
Pruning the Tops of Plants
I am growing indoors for the first time. I have a few good plants that are about a month old. A friend told me to cut the top but I wasn’t sure where to cut exactly. Right now, they all have about four leaves with new ones coming up. Is that what I cut? Any pointers will be appreciated.
Do not prune the tops of indoor marijuana plants unless you want to retard the harvest. Outdoor plants can be pruned, but best to do it early in the season before branches get rigid.
Leave the plants alone! They are only a month old and hacking up healthy plants will not make them grow any faster. The plants need nurturing now not pruning. In fact you said it yourself “I have a few good plants.” Concentrate on making them grow big healthy leaves and later big healthy buds. The plants should be about a 30 cm tall and have more than four leaves. The most common causes of slow growth the first two months of growth include lack of light, poor soil, over-watering, poor ventilation and temperature control. Make sure they are getting everything they need in the proper proportions. If you are using a 400w HID the lamp should be about 45 cm above the plants. It can be moved closer (30 cm) when plants are a little older. It is a bit late to change soil now. Always use the best store-bought soil you can find. Most soils benefit from adding 10-15 percent per lite to speed drainage, which will also help with over-watering. Increase ventilation and circulation so that all of the air changes in the grow room every 1-5 minutes. This will also help ensure plants transpire properly. Keep the temperature about 25 degrees during the day and about 22 degrees at night.
Turn the lights to a 12/12-hour day/night schedule when they are 8-10 weeks old to induce flowering. If plants are too tall and leggy, consider bending them so that more foliage receives light. Bend plants so that the canopy of the garden is on the same plane. Once you harvest a few crops successfully, you will realize that controlling the basic needs of plants is just what your plants need.