Last week we looked at the first two components of “Mel’s Mix," sphagnum peat moss and vermiculite. Today we’ll talk about the third, blended compost, and learn how to make the mix.
We learned that the peat and vermiculite help by holding in moisture while still allowing for good drainage, oxygenating the soil and keeping it loose and friable (crumbly). Think of a sponge. When you slowly add water it reaches a point where it is full saturated. After that, if you add any more water, it just runs out. But neither of these ingredients provides something very important to your plants.
The blended compost is what gives your plants all the nutrients they need. Of course the very best compost is one that you make yourself and control the individual ingredients. We will probably get deeper into the subject of composting in the future, but for now I’ll just say that making your own is optimal and costs the least.
If you can’t or don’t want to make your own, then you need to do a bit of homework. Don’t buy just one type of compost, no matter how fabulous the person at the nursery tells you it is. In general commercial compost is the byproduct of a single industry, wood shavings, cow manure, soybeans, etc. It used to be that the lumber works or the cattle rancher had to pay to have someone haul off their waste. Then they discovered eager gardeners are willing to pay a good price to take the finished compost off their hands.
Since the compost from a single industry doesn’t contain all the needed nutrients, you need to gather it from different sources and mix or “blend” it yourself. Those “fabulous” blends you find at the home store or nursery usually contains a significant amount of peat moss and this will throw off the proportions of your Mel’s Mix—remember it is 1/3 each of peat, vermiculite and blended compost.
A friend of mine was about to buy something listed as a five way compost suitable for square foot gardening at a large home-improvement store. When she pressed the sales representative, they called the manufacturer. The manufacturer finally admitted that this product was "not more than 90% peat and not less than 10% blended compost." That sounds to me like she was buying peat and NOT compost. Buyer beware!
One of my favorite sources for compost is Veteran Compost in Aberdeen—I will do an article about this great company really soon. For my SFG4U business I exclusively use their food scrap/yard waste compost and mix it with some of their worm compost. Just the other day I was bagging some compost I got from them MONTHS ago and there were worms in it! So my customers sometimes get a bonus.
Please make sure you take the time to collect at least five different sources of compost or find a reputable composting operation so that your plants get the optimal nutrition and mix/blend it thoroughly.
Although we have talked about blended compost being 1/3 of Mel’s Mix, MAKE EXTRA and store it for future use. You will not need any more peat or vermiculite, but because this is a high-intensity form of gardening, you will need to replenish the nutrients in your mix by adding a large trowel full of blended compost after you harvest each square throughout the season.
So, now you have peat, vermiculite and compost ready to go. Let’s see how to make your Mel’s Mix!
Spread a large tarp on the ground (it’s best to do this near the raised bed you intend to fill). Put equal amounts of each ingredient on the tarp. To make sure you have equal parts of peat, vermiculite and compost, it’s as easy as using a 5-gallon bucket to measure a “scoop” of each. Don’t forget you MUST “fluff” the peat moss (break it apart) thoroughly before measuring. I have to tell you, I find this is the hardest part of the entire process especially when using professional or commercial bales of peat as it is super compressed and hard as a rock. If you find an easy way to break up your peat PLEASE share the info!
After putting a “scoop” of each of the three ingredients onto the tarp, you will want to very gently mist everything with a garden hose—just enough to knock down the dust a bit, do NOT wet it too much or it will be too heavy. Next you and a friend each take a corner of the tarp and “roll” front-to-back then side-to-side until it’s thoroughly mixed. (See the photos)
I mix so much of it for my business that I find it easier to use a small cement mixer.
Once again, if you happen to be at the MD Home & Garden Show Sunday 3/11 at 12 PM stop by and see my free seminar on Square Foot Gardening.
If you can't make it to the show, I'm holding classes in Glen Burnie on Saturday, March 17th. SFG 101 (Intro to SFG) will be 10 a.m.-noon and SFG 201 (Continuing SFG) will be 1–3 p.m. Register or contact me online at sfg4u.com. Class size is limited to 10 people so register early. The same classes will also be offered April 21, May 19 and June 16.