Veggies in shade of mature Ponderosa Pine with morning sun?
Dear Master Gardener,
Do you have suggestions for vegetables that can be grown under the drip ring of a mature Ponderosa pine, in soil that receives morning sunlight?
Given how pines seem to kill everything beneath them, I was wondering if you had suggestions.
Arapahoe County Colorado
Growing vegetables under a Ponderosa pine is not a good idea for several reasons.
Most vegetables require full sun, which they would not receive under a pine. Receiving just morning light would not be enough light for most vegetables to grow and produce.
Air flow under trees is very limited. Vegetables would likely suffer from powdery mildew which is caused by lack of air flow.
Anything that is planted under a tree competes for water and nutrients. Vegetables require a lot of both, and the tree would be absorbing those.
Depending on the vegetable, digging them to harvest would disturb the soil, thus affecting the small feeder roots of the pine that live in the top layer of soil.
Not a lot of plants can survive under a pine tree because the level of shade is high, and the pine needles can smother plants if they are not continually cleaned up. Mulching around the drip line of the tree is a good solution. Either an organic mulch such as bark chips, or simply leave the pine needles as mulch.
If you want something planted under the tree, a shade-tolerant lawn (such as fine fescue) or a shade-tolerant ground cover is best. Again, for the ground cover to thrive, pine needles will need to be cleaned up as to not cover (and smother) the plants. If you plant a ground cover, purchase smaller plants. Larger plants require larger holes and can disturb the tree roots when planting. Here is a CSU fact sheet on shade tolerant ground covers. There is a section for part shade and deep shade.