Episode Details

Interview with Robert Pavlis of GardenMyths.com:

Can Human Food also be Plant Food? (It depends how you apply it.)

(originally aired in Episode 126 of the Garden Basics Podcast)

Farmer Fred: What do you give plants to drink besides water and plant food? This question actually has been asked on many social media outlets, and in many gardening groups. And you might be surprised at the number of household kitchen products that are given to plants. Are they worth it? There is one gentleman who actually tackles a lot of garden myths. He's even written a book on the subject. It's Robert Pavlis. He's a well known speaker-educator, with over 40 years of gardening experience. He's the author of several books including "Building Natural Ponds", "Soil Science for Gardeners", and "Garden Myths". And he publishes the popular gardening blog, gardenmyths.com as well as garden fundamentals.com . He gardens in Ontario, Canada, and Robert Pavlis, it's a pleasure to have you on the program. Tell us, for those of us who aren't familiar with gardening conditions in Ontario, Canada, exactly what your seasons are.

Robert Pavlis: Well, we have a USDA Zone five garden, so we have a fairly long winter. Around here we don't get great snow cover but we do have snow and then we have hail and sleet and everything in between. And then it gets warm and then it gets cold. So even though our winters aren't that cold, the problem here is that we have this freeze-thaw problem. Then spring comes, the summers are quite humid, quite hot. So today is 29 degrees centigrade (84 F). And fall comes pretty quick. And you know, by middle September, while things are finished in the garden by October, we could have frost.

Farmer Fred: So if you're going to grow a summer vegetable garden there, you start around Mother's Day and wrap it up by, I guess, the end of September.

Robert Pavlis: Yeah, well, our traditional last frost date is May 24. That's moved back now to around May 10. So a lot of gardeners up here will try to extend that season. So we use things like rowcovers, or we gamble, what I call gambling in the garden. And I plant things two or three weeks early and hope it doesn't freeze. But that doesn't always work. And we try various other ways to keep things a little warmer. But yeah, early May. Tomatoes and warm season crops, they probably won't go out until late, middle-late May, depending on the year.

Farmer Fred: All right. So a bit shorter than here in California, to say the least.

Robert Pavlis: Just a little bit. Right.

Farmer Fred: All right. Well, I love your GardenMyths.com column that you post, and people can subscribe to it. It's free, and you get email notifications when they are released. And awhile back, you had one on feeding plants from the kitchen, discussing which products actually work. And for those of you who are short of time, the quick answer is, "not many". But I am amazed, though, at what food scraps people are feeding to plants that they think will work. I guess we should start off with discussing exactly how plants absorb nutrients.

Robert Pavlis: Plant roots only absorb certain things. And they have to be what I call small molecules. So nitrogen, potassium, phosphate, these are all small molecules. But what you have in most plants is large molecules, proteins, carbohydrates, and so on. And you can put all that you want on a plant