Fertilizing Ponderosa Pines
Jimmy needs to know what kind of fertilizer is recommended for Ponderosa Pines (12' tall, 3 years old); and watering plan at this time of year?
Humboldt County Nevada
It is actually best not to fertilize pines unless you are specifically adding a nutrient that is missing in the soil. If he is just looking to improve the health and vigor of the tree the best thing is to add good quality compost around the base of the tree extending out beyond the dripline.
If he wants the trees to grow more quickly then he must make sure he widens the area that he is watering and he could use a 10-10-10 around May.
Watering right now varies on accumulated moisture from nature and the soils that the tree is planted in. I would suggest a deep soaking at least once a month when we do not have snow on the ground for long periods of time. If he is in clay soil, he will need to be careful that the tree does not drown or have water that freezes and thaws around the trunk.
This fact sheet from Colorado will provide a few good tips, but he should keep an eye on soil moisture and moisture accumulations.