Bogs are a fascinating addition to any garden!
Do carnivorous plants such as pitcher plants and sundews tempt you, but unsure how to grow them? These plants are so cool, but are only suitable for containers or man-made bogs. Customers often admire our bog plants during the season, but hesitate due to their seemingly complex care. But, bog plants are not that difficult to care for and their conditions are easy to provide if you install your very own bog garden!
First of all…what is a bog?
A bog is a type of wetland, which over time accumulates dead plant matter, called peat. Peat is a composition of plant materials, often a majority of sphagnum moss. As the sphagnum grows and dies, the deposit grows due to low oxygen content and acidity of the saturated soil. The wet soil of the bog is rather infertile because of the lack of decomposition. Break-down of organic materials is so slow in bogs, animal and human bodies have been found “mummified” after being buried there for hundreds of years.
Though infertile, these bizarre landscapes provide habitat for distinctive groups of organisms including many animals, fungi, and of course, plants. Carnivorous plants are perhaps some of the most famous bog dwelling species. These plants have adapted to these inhospitable conditions by extracting the majority of their nutrients from insect prey instead of the peat. North American pitcher plants (Sarracenia), sundews (Drosera), Venus fly trap, common butterwort, and bladderworts occur in bogs in the Eastern United States. But, there are many species of plants that live in bogs. These include ferns, mosses, horsetails, rushes, sedges, grasses, heath members, conifers, gentians, lilies, and a wonderful assortment of orchids. Cranberries also grow in bogs (member of the Heath family), and is easily grown in a home-made bog! That said, the potential for a bog garden is limitless.
So, a bog can be created?
In short, yes! While we can’t efficiently recreate natural bogs, we can create bogs in our own backyards! In fact, the massive bogs that cranberries are grown in are man-made too!
Simply put…to build a bog, you build a pond, but instead of water, you fill it with peat and sand. Building an in-ground bog allows you to enjoy your bog plants with ease. Growing bog plants in containers is very doable, but can be a lot of work to keep up with watering and repotting. Plus, by building a bog, you can create your very own custom size and shaped bog to fit perfectly in your garden!
This is how I came to build my own bog garden in 2020. Watering numerous containers, and repotting plants that quickly outgrow their containers grew quite cumbersome. Now, over a year later, I want to share my creation and inspire other people to build their own bog garden!
What kind of special care do bog plants need?
As you now know, bog plants require a specific soil to grow in. If you can provide that by building a bog, the rest of the care is very simple.
Soil (or, media):
Soil is a natural product of the earth, it takes thousands of years to build a layer of topsoil. Bog plants do not like soil, because they do not grow in it in nature. Instead they grow in saturated peat. When you make a “soil” out of various natural ingredients for gardening, we refer to it as media. The media you will use for a bog should comprise of peat and sand. Peat can be purchased at any garden center, but be careful not to buy peat that has added fertilizers or pH buffers…just plain ole’ peat moss. I used all purpose sand, which again, can be purchased just about anywhere, but you could also use silica sand. I would avoid play sand.
Mix the peat and sand in a 4:1 ratio (80% peat and 20% sand). Of course, you do not need to be precise down to the gram here, a rough estimate will do. Be sure to mix the media evenly, breaking up big chunks of peat.
Water is critical for bog plants, for not only are they dependent on a lot of moisture, but they are also “picky” about their water. You see, given the conditions in bogs, any water that flows into the bog is filtered by the peat. And, since the peat does not decompose into true soil, minerals such as metals are not present.
Therefore, bog plants can be very sensitive to minerals, such as iron, sodium, and calcium. These minerals are often found in groundwater (tap water), and so I do not recommend using your hose to water your bog. The best water you can use is rainwater, or distilled water. You can also use the water from your dehumidifier if you have one. If you plan to create a big bog that could need a lot of supplemental water, consider installing some rain barrels.
Pay attention to the moisture levels in your bog. If you allow the media to become too dry, you may force your plants into dormancy or kill them. Since bogs are a wetland, the plants require high levels of moisture. Check often in the summer, especially during drought. If supplemental water is needed, water slowly to avoid displacing your media or plants. If your bog is deep enough, it is likely that you will not need much supplemental water. I only had to water my bog once in the hottest part of summer, which I find quite miraculous considering we had a bout of drought in 2021. Watering is a huge chore for container bog gardens, and I found the biggest plus of creating an in-ground bog was how much time I saved on watering.
It is advisable to cover your bog garden with a layer of pine needles in the winter to provide protection to your plants. While many bog plants are native to Pennsylvania, and winter hardy, conditions in your man-made bog will differ than those in a natural bog for winter. I collect up some buckets of white pine needles after the trees shed old needles in fall, and put about 6 inches over my bog. My flytraps and pitchers all came back fine in spring, despite living on the border of zones 5B and 6A (Carbon County).
Remember snow is good. It insulates the plants and soil below it. It is one of the most effective forms of protection, so don’t feel bad piling some extra snow on it. Plus, when it melts, the bog will capture the moisture.
Building an in-ground bog garden is so much easier and dependable for overwintering plants than containers.
Unnecessary and most often harmful. Most fertilizers will kill sensitive bog plants, so just avoid them. Carnivorous plants are gluttonous, and eat a lot without our help, so you need not worry about that. At the end of the season, you can clip back pitcher plants and dissect the pitchers. It is incredible how much insect matter builds up in the pitchers, you have to see it to believe it!
How to create a simple bog garden, step by step:
- Pond liner
- peat or sphagnum moss (be sure not buy a product with a pH buffer or added fertilizer)
- coarse, all purpose sand
- decorative rocks (for edging bog)
(Size and or amount of materials depends on size of bog)
- pick (helpful)
- scissors (for cutting liner)
- wheelbarrow or trailer (for moving soil and mixing bog media)
Choose an appropriate location in your garden to site your bog. Bog plants generally require full sun (6+ hours of direct sunlight per day). It is wise to site your bog in an area that is convenient for watering, when necessary. If you have a rain barrel, site it near there, because that is the water you will want to use for your bog. Since you will dig a hole, be sure not to choose a spot with buried electrical, water, or gas lines. Also be careful of nearby trees and shrubs so you do not damage their roots.
I placed my bog on the east side of my house, and it receives direct sunlight until almost 2pm in the summer.
Mark out your spot, and design the shape of your bog. You can tweak the shape as you dig, but it is wise to use ground marking paint or flour to draw out the basic shape of your bog. Keep in mind, the bigger the bog, the more soil you will have to move. But, I am also a firm believer in “go big or go home”; you may regret making it too small. Adding new plants to your bog can be a little addictive (this is your only official warning).
Dig the hole!
I decided to go basic with my first bog by making it rectangular, roughly 5 feet long x 3 feet wide. I dug the hole 20 inches deep. It is recommended your bog br at least 18 inches deep, to leave adequate room for root growth. The deeper you make the bog, the more water it will retain and less supplemental watering it will require. Since my bog is almost 2 feet deep, I only had to add water once during the hottest, driest part of summer. I decided to make the sides flush, rather than tapered to maximize space.
Once finished, pour sand directly into the hole and spread it evenly to create a 1″ layer of sand to buffer the liner from the rough, rocky soil below.
Place a brick border around the hole. This elevates your liner slightly above the surrounding soil, so natural soil from your garden does not get into your bog.
You could also build a wooden frame out of 4×4 lumber, but I had these old bricks laying around. Note, these bricks are 12in in length, and are larger than a standard red mason brick. Bricks are also more cost effective than lumber purchased new, plus will never rot, so I recommend them regardless.
Place your pond liner. Place your pond liner in the hole, but do not trim it yet. Leave the extra material overhang the sides of the brick border for now.
I bought this liner at Lowe’s, I think it cost around $25. You could buy a plastic pond form, and simply install it as you would if you were to use it as a pond. However, pond forms are expensive and can not be customized. So, I recommend going for a rubber liner like I used.
Mix your media. In order to create an appropriate bog soil, mix peat and sand in a 4:1 ratio (80% peat and 20% sand). Be sure to purchase plain peat moss, with no pH buffer or added fertilizers. The sand you purchase should be all-purpose sand, but you can also use silica sand if it is available. As you mix it, wet it. Peat moss is hydrophobic once dry, and is difficult to rehydrate. Hydrate it as you mix it, and do your best to get it saturated. Though bog plants are sensitive to excessive minerals in tap water, you can use tap water for establishing the bog. This way, you can work with the hose next to you. Just don’t use the hose for supplemental watering once your bog plants are installed.
Fill your bog with your media! You should fill the bog all the way, and try not to leave gaps and airspaces, really pack the media in there. Mound the media slightly above the level of the liner, as it will settle over time. Once filled, you can trim the extra liner back to the bricks. Be sure to leave some liner hanging over the bricks.
Cover the liner edge with rocks or decorative bricks. This will keep the liner from slipping over time, and create a pretty border between your bog and the surrounding garden.
This is the hardest step. You may need support during this time. For those who lack patience, I am sorry. This is the point where you wait. I advise waiting at least 4 weeks until you add plants. I know, this is torture for all of us. However, you can use this time to shop around and build up a collection of plants that you will add to your bog. Just care for them in their containers until your bog is ready to be populated.
Add your plants and enjoy!
Placement of plants depends on the orientation of your bog. I decided to place my plants randomly, to give my bog a more natural look. All I can say is to pay attention to the mature sizes of the plants you choose to include, and space them accordingly. These plants are gorgeous, so be sure to give them the justice they deserve.
Here are a couple photos of my bog a year later, with my plants thriving! Some of them I planted in 2020 about a month after creating the bog, while others I added in 2021. You can see how in just one season, the plants in the bog seemingly exploded with growth!
(To all the native purists out there offended by my petunias, my apologies)