This week's GardenLine tip is another on the subject of peat moss, sphagnum peat moss, and why they should be avoided in Southeast Texas landscape beds. What follows is an overview of material I've compiled from other experts, specifically Mary Cummings at RCW Nursery and Linda Gay at The Arbor Gate.
Call it a compilation, call it creative plagiarism, but whatever you do, don't use peat-based products in your landscape.
"Organic" garden soils or "organic" raised bed soils derived of sphagnum peat moss and processed forest products have a GREAT water-holding capacity - like a sponge. The job of peat and sphagnum is to hold moisture in the soil around plant roots. But when the soil stays wet and cannot dry out, plants cannot produce sugars (food). Essentially, they drown.
In addition, if peat-heavy soils dry out too much, they create an impenetrable barrier at the top that sheds water. Thus, no moisture percolates down into the soil. I see this often in my consulting business. In fact, here's a picture from one of my most recent consultations in West Houston. See how two of the top three ingredients are peat-based?
There's also the "environmental" slap in the face. Peat moss is the partially decomposed remains of sphagnum moss harvested from bogs. As Mary Cummings has written, "… the biggest problem with peat moss is that it's environmentally bankrupt! It is essentially "mined" by scraping off a bog's top layer of living sphagnum moss. Despite manufacturers' claims that bogs are easy to restore, the delicate community of animals and insects that inhabit a bog cannot be quickly re-established. Yes, peat moss is a renewable resource, but it can take hundreds to thousands of years to form."
Here's my simple rule: If the first two or three ingredients listed on a bag of soil are peat moss or sphagnum peat moss, avoid it at all costs. You and I alone may not be able to change the environmental degradation resulting from peat bog harvesting, but if more of us use peat-free products, like those I endorse, maybe the message will be heard.
Peat is not the amendment we need to use in clay soils — we need to add more compost and shale for improvement. If you don't understand why small rocks or shale should be incorporated to create pore space, here's a great analogy by Linda Gay. "PEOPLE GET IT - WHEN PUT INTO WORDS THEY CAN UNDERSTAND WITHOUT GETTING TOO TECHNICAL!! I had a customer who asked how she could convince her husband to buy rock and work it into the soil, and I told her, 'the soil has C.O.P.D. (Chronic Obstructive Pulmonary Disorder), and the rock will open up the airways for the plant to breath.' She totally understood that analogy and was on her merry way!" We cannot see soil air spaces, just as we cannot see our lungs. We can only see whether plants do well or not.
If your plant hasn't grown two inches in two years, that automatically tells me there are no air spaces for the roots to grow, so the plant just sits and eventually declines.
We create air spaces by adding permanent amendments like expanded shale — this porous pebble "breathes" with the plants during respiration, and the process is dependent on available oxygen.
As we are most often gardening in heavy clay soils or small-particle sands, every time we put a shovel in the ground, we need to add compost and expanded shale to create more air spaces. You only get one shot at getting the planting right! My advice for years has been to start with quality rose soil at the very least. It has humus or compost in it, but the ones I recommend have never had any kind of peat.
The Arbor Gate has a proprietary soil blend called Organic Soil Complete. It's called "Complete" because it has every component needed to grow thriving plants in our clay soils. Key is the fact that it has compost and large-particle sand that help to grow a really big root system, requiring minimal watering and daily care. There's also expanded shale in this soil blend, adding a permanent porous pebble that receives and releases air and water in the soil during the wetting and drying process.
For the record, there are a few products I endorse that have some peat moss in them, but it's around 10 percent of the whole product. And I still don't recommend those for landscape beds — just for potted plants and hanging baskets.
Grand Opening of Fulshear Ace Hardware on Saturday
I will be on hand 11 a.m.-1 p.m. Saturday at the newest local Ace Hardware store, 8411 Main St. in Fulshear.
Our visit is being sponsored by Nitro-Phos, which means we will have drawings to give away free bags of Nitro-Phos fertilizers while I'm there. You don't have to be present to win, but you have to register between 11 and 1. If I draw your name and you have already left, we will call you and you can pick up your prize at your convenience.
The opening of this store is awesome news for the Fulshear area, because that area has never had a retailer that follows the advice in my fertilization schedule. So you can now pick up many of the products I endorse without having to leave town.
This is a brand new Ace store, so they are just learning the ropes of the GardenLine fertilization schedule. But with my help, the help of the Greater Houston Ace Retailer Group, and the help of distribution points like the Nitro-Phos warehouse, they'll soon be up to speed and carrying the vast majority of the basics I recommend. They already have copies of my book, "Texas Tough Gardening," and I'll be bringing along more this Saturday to sign for all my new friends in Fulshear. The real question is, who's gonna bring me some ribs from Dozier's?