Frequently Asked Questions About Landscape Gardening

I am looking to create a circular flower garden in my backyard. I also really enjoy the look of retaining wall stones that have become so popular in recent years. I’m wondering if there is a way that I can get help figuring out a certain calculation or if there are any websites that can help me calculate the amount of materials that I will need for the project. In addition, I also need assistance in keeping the overall spacing exact just enough to ensure that both levels come to an exact block count in order to keep from having to cut the blocks themselves. The retaining wall blocks I have are designed with lips both on the back and the bottom of the blocks, which will cause the circle to get smaller as each block gets put on. Is it a good idea for me to chisel the lips off of the blocks since they won’t be able to support much weight?

A: You should measure the length of the block then divide it into the overall perimeter of the flower bed, but please note that the number will not be an exact one. The majority of the blocks are longer along the midline of the length solely for flexibility. You will be able to come up with whole blocks by adjusting the overall perimeter. For example, a flower bed that measures approximately 16 feet would have a diameter of 50 feet. This would then be divided by the 16 inch length of a block, the end result of which would require about 37 blocks to lay the perimeter. Also, each course of blocks will always take the same number. You will need to multiply the diameter by pi (3.14) in order to calculate the perimeter. While it’s entirely up to you, you should consider leaving the block lips in place, as a three-course wall would look much nicer with the setback.

Q: In my small front yard, I currently have a nice stand of Bermuda grass; however, it cuts unevenly due to the soil being uneven. I would like to level the soil, but was wondering if there were any useful tips for smoothing out the dips. Can you help me?

A: You can add materials such as different mixes of sand and potting soil or even potting soil itself to the dips. This should make the Bermuda grass grow readily into the space. The grass should also adapt to the deeper soil as well as “move up” to grow in the deeper soil thanks to the new materials being added.

Q: If there is dirt left behind from holes that have been dug up for fence posts, how can I remove it without killing the grass?

A: The best way to remove the dirt would be to either lightly spread it around the yard or put it in any low-level areas of your lawn. If you currently have warm-season turf, then grass should grow without any issue. However, if you have cool-season turf, it’s a good idea to re-seed the dirt. You will not need to re-seed the dirt if it is spread out lightly on the lawn

*From our expert gardening advisor Susan Patterson: “When digging holes for fence posts always put the dirt in a wheelbarrow or on a tarp so that it does not damage sod or your favourite rattan chair.”

Q: I am currently planning on redoing my backyard in the spring, and I’m looking for a few tips to help me out along the way. When the previous owner lived on the property, he had the driveway built so that it sat a few feet above the backyard, which ended up leaving a drop of a couple of steps from the driveway to the yard. We would like to use some dirt in order to slope the backyard up to the driveway before re-planting the entire backyard. My question to you is this: what is the best way to kill grass that is currently in the yard in order for us to be able to successfully re-plant it next spring?
A: Unless you have quack grass or something similar to it, the soil that you plan on importing will kill any turf underneath it if there is a depth of one inch or more. One of the best herbicides that will have an effect on most weeds and grass types is called Roundup. With this, you can perform a blanket application to kill off everything before sodding or re-seeding seven to ten days after applying the Roundup.

It’s important to note that in order for grass seeds or sod to germinate, a ground temperature of at least 60 degrees Fahrenheit is needed. The seeds or sod will germinate in as little as five days to one month depending on the type of seeds or sod you select. You will also need to allow approximately one month or an entire season to fill everything in and become usable. If you need assistance with selecting the right seeds or sod, you can contact your local Co-operative Extension or County Agent.

You also will want to hold off on bringing in the extra dirt until you are fully ready to seed and/or sod due to the possibility of heavy rains washing everything away. Sodding may also be preferable to seeding on sloped areas.

*From our expert gardening advisor Susan Patterson: “If you are looking to kill an area of sod without using a chemical you can cover the area with black plastic and smother the grass.”

Q: I currently have some bare spots in my yard that are completely covered with creeping juniper plants. When do you think is the best time to re-plant? How should I prepare?

A: There are three qualities about creeping juniper plants: they are easy to grow, drought-resistant, and require low maintenance. During the springtime, you should be able to find them in your local garden center. Begin the re-planting process by digging a bowl-shaped hole that is twice as wide and deep; however, be careful not to dog the hole too deep as this will cause the plants to settle too deep. As you dig the hole, be sure to mix in a layer of either compost, planting mix, or any other kind of organic matter that measures approximately two inches deep. Cover all of the topmost roots with approximately 1/2 an inch of soil, avoiding piling mulch or soil around the main stem of the plant. Ensure that you take the time to water the ground and the plants themselves before planting them. Spread a deep blanket of mulch approximately two to three inches deep in order to keep the soil moist and control the weeds, but only after the dampened ground settles.

Q: I currently have holes in my sod caused by either the rain not properly settling the dirt or me not compacting the ground enough. Some holes are large while others are small, kind of like a footprint.

A: The sod should have knitted to the soil within approximately two weeks if the soil had been raked flat and smooth, as well as being properly sod-rolled and watered. During the late springtime just before grass growing reaches its prime, holes can be plugged with sod. It may also help to re-roll the lawn itself.

Q: When I look at many landscaped areas, I can easily see that the areas around trees are in near-perfect circles. I have tried using both a shovel and an edger to dig it out, but I can never make the circles look nearly as good. What can I do to achieve this?

A: One useful method is to use a tape measure, measuring out from the tree trunk to ensure that the bed’s depth will be the same all the way around the tree itself. Mark the locations with stakes and use a material such as flour to outline exactly where you want to dig. Using a shovel, press into the soil along that line, ensuring that the edge along the perimeter is a little deeper to keep mulch inside and looking tidy.

You can maintain the area by using a flat spade, half-moon edger, or even a weed trimmer.

Q: There are a few rocky areas of my property that always get sun, but right now, they are mostly all weeds and dirt. I’ve considered renting a rotor tiller to help make the ground soft in order to plant seeds, but what is the best method to get rid of all of these annoying weeds?

A: Begin by loosening the soil and removing rocks. You can either pull the weeds or cut them before spraying them with an herbicide such as Roundup. If you cut the weeds, they will grow back within a couple days. If you spray the herbicide on the new weed growths, this will be the best way to apply it.

Q: A wooded area is located at the back of my property. Sometime within the next week, I will be removing the stumps of trees that I have thinned out. The area is almost entirely clear of weeds thanks to using some of the Roundup herbicide on them. I’m considering just simply tilling the remaining weeds and placing two to four inches of new topsoil around the area before seeding it with grass. Will the grass seed essentially choke out any new weeds that may attempt to grow while I’m watering grass at the same time? Should I make sure the weeds are completely dead first?

A: Your best option would be to spray the herbicide once more. The next day, till the area and apply the topsoil. You will want to ensure that you deal with any weeds that may sprout from the soil that has been tilled and reposition the grass seeds you place. You may also have to deal with weeds that pop up when the grass grows as well. Once the grass becomes thick in nature, the weeds will all eventually choke out.