Gardening expert Charlie Nardozzi shares his expertise each week and answers listeners' questions about gardening, house plants, veggie starts and more. This time, we'll get some facts on how to choose the best potting soil.
Picking out potting soil from all the varieties available at your favorite local garden store or home center can be daunting. It helps to think of your potting soil needs as falling into one of three categories:
1. Starting seeds indoors: If you're starting seeds indoors, get seed-starting mix. It's light, fluffy and ground down into a finer texture. This makes it so germinating seedings can push through it more easily.
2. Specialty plants: If you have a specialty plant, like a cactus, an orchid or an African violet, get specialty plant mixes. These have beneficial nutrients that enhance the soil and aid in keeping your plant happy and thriving.
3. Everything else: In this case, the "everything else" category includes house plants, trees, shrubs, and anything you're transplanting or repotting. For these tasks, get an organic potting soil. These soils contain compost and organic fertilizers so the nutrient value lasts a bit longer. The compost helps with water drainage and retention.
Can you use leftover potting soil from last season? You can, so long as last year's plant or veggie didn't have fungus or insects. If that's the case, just compost the old mix and start anew.
Q: I have an avocado plant that I raised from a seed. It’s about three feet tall and branching out. However, some of the bottom leaves are turning brown at the tips and edges. What do I need to do? — Jock, in Eden
You should repot the whole plant. Use fresh potting soil or, if you've recently repotted and the leaves are still brown, try flushing it out. Sometimes browning on the leaves is from fertilizer salt residue that remains in the soil and can burn the leaves, causing them to turn brown. To flush out your plant, just water it thoroughly until the water runs through.
Q: What do you mean when you say, "fertilize regularly"? — Catherine, in Middlebury
The answer to that really depends on what kind of gardening you're doing: If you're out in the garden and you put compost down in the spring, along with an organic fertilizer, you're probably good for the whole growing season.
For containers, "fertilizing regularly" usually means once every few weeks or so, depending on which fertilizer you're using. A good tip is to check the fertilizer mix label and follow that.
All Things Gardening is powered by you, the listener! Send your gardening questions and conundrums (and pictures!), and Charlie will answer them in upcoming episodes. You can also leave a voicemail with your gardening question by calling VPR at (802) 655-9451.
Hear All Things Gardening during Weekend Edition Sunday with VPR host Mary Engisch, Sunday mornings at 9:35.