Edging and decorative rock materials may have different names, depending on the manufacturer of the edging, or where the rocks are from. As I said in the beginning, landscaping varies depending on the region you live in. Availability and cost of materials varies as well.
It can be confusing when you read about different materials in a book, and then go to purchase them only to find out they don't have what you want. They may actually have it under a different name. I will try to be as generic as I can describing materials, to avoid confusion.
Landscaping rocks can be sold in different ways, but most decorative rock is sold by the yard. This way you can estimate your requirements based on the dimensions of your project.
I have found that the yards themselves have different suppliers and pricing for edging materials with some being a better quality than others. Using a better quality edging will look better and last longer, saving you time and money down the road. Landscape fabrics (weed mats), also come in different qualities.
Landscaping with gravel or rock that is smaller, is more practical than larger rocks if you are going to be walking on it frequently. Also, crushed rocks or gravel will have more mechanical bond from the broken and jagged edges.
Round rocks will tend to move apart and slide around more making it difficult to push a mower or wheelbarrow through. Garden mulch or bark mulch for these beds should also be selected and used in a practical way. (Don't use it in high traffic areas or where high winds exist.)
Some rocks can leach or (Bleed) toxins into the soil or change the pH level (Limestone). Choose your decorative rock carefully if you are planting in and around your project. Granites are a safe choice.
Enquire about the yards return policy if they have one. You may have some materials left over. When landscaping with rocks and fabric it is important that the decorative rock they sell is clean. Although it is almost always sold washed, I have found some yards do a better job than others. The cleaner the rock is, the less silt and sediment will be on your clean landscape fabric. This means blown in weed seeds stand less of a chance of rooting.
Now that you are a little more familiar with stone yards, you are going to have to estimate how much edging and decorative rock you will need. To estimate the amount of rock requires you to know the dimensions of your area, so you can figure out the square footage. Once you have this measurement, the stone yard will be able to tell you how many yards you will require. The formula is as follows:
Multiply the length times the width times the depth, and divide by 27 and this gives you the yards of rock required. You will also have to divide the number of inches in depth by 12. (There are 12 inches in a foot). This will give you the .25 in the example you see below.
Eg: An area that is 20 by 20 with 3 inches deep of decorative rock,
20ft times 20ft = 400 sq. ft
multiplied by .25 (¼ of a ft.)
= 100 sq ft divided by 27 = 3.7 yards
Stone yards don't usually sell anything less than ½ yards unless they have a scale. But I always recommend rounding this number up a little bit anyway. In this case, I would go with 4 yards.
To buy the correct amount of edging is just a matter of measuring the outside perimeter. Edging can come in many different lengths. It can sometimes be sold with connector pieces and metal stakes as well. I recommend purchasing an extra bundle (4) of metal stakes, for every 20 feet of edging that you buy. Having these extra pieces keeps the edging more stable (especially on curves).
You are also going to need some landscape fabric. This is another material that I recommend spending a little more money on for good quality material. I use an industrial strength woven fabric sold at landscaping yards. They should have small rolls for do-it-yourselfers, 100 to 500 square ft. rolls. Make sure you also purchase a good supply of landscape pins. These secure the fabric so it doesn't slide around. (Very helpful too if you are installing it on a windy day.)
Hopefully, you have the area all planned out with the dimensions. This is a good time now to plan out what and where you are going to plant (if anything) in the decorative rock. Remember to keep a nice rhythm and line when you are planting.
Now you should have all the tools and amounts of materials that
you will need to do the job, it's time to move on the the next stage of
preparing the site.
Table of Contents: Edging and Decorative Rock
A. Edging Site
B. Edging Tools
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