Before beginning to create and plant a bog garden, the type of soil present in the desired area needs to be ascertained. If there is a lot of clay subsoil, then a very small amount of water everyday will keep the area sufficiently moist. If the subsoil is light and well drained, then the area will need to be excavated and different soil added before the bog garden is planted. A bog garden needs full sun for at least five hours a day and should preferably be away from tall trees.

Natural bogs have a very low oxygen level which does not allow dead plant matter to decay. The leaves and twigs that fall build up in a thick layer which becomes peat. In natural bogs, the water comes mainly from rainfall which causes the ground to be acidic and have a low mineral content. It is the combination of full sun and constantly moist ground that support the plants specific to bog gardens to grow to optimum beauty.

The best place to create a bog garden is in a place that naturally collects water and has enough sunlight. If a bog garden is desired but a naturally wet spot does not exist, a spot can be created in a place with enough sunlight. A constant natural source of water would be ideal, however, this can be arranged through watering. For the plants to reach their peak, the garden should never experience drought.

First, the basin should be prepared. One to two feet of soil should be removed and the sides of the basin should be straight. If the garden has problems with tunneling rodents, the basin should be lined with a galvanized hardware cloth or screening or weed cloth. Make sure the material is rot or rust resistant. On top of the screen, 4 to 6ml plastic sheeting should be put. Make sure it is large enough, because the edges can be trimmed after installation. In the base of the plastic liner, cut ten-inch slits every 10 – 12 inches to allow drainage. Most of the moisture needs to be kept in the bog, but it shouldn’t get stagnant, this is why drainage is important. Two to three inches of wet river sand, not beach sand, can be put on top of the plastic liner.

After the initial preparation, the basin can be filled with a well mixed combination of one part coarse river sand, two parts peat based compost and one part loam based soil. The mixture should be damp and can be tamped in place to reduce settling. The basin should be filled to one inch or so below the existing soil level. The lining can be trimmed to near ground level, then hidden with rocks, garden ornaments and mulch.

Almost any moisture-loving pond plants will thrive in a bog garden. They can be found near streams and ponds and even growing in the water. Most plants for bog gardens need to be planted in the spring or autumn. Some plants that love marshy areas are Bog Myrtle, Bee Balm, Cranberry, Sundew, Blazing Star, Cardinal Flower and Pine Hibiscus. The tall plants should be planted in the back of the bog and the small plants near the front or viewing area. Three or four plants of the same variety should be planted together for a natural effect, and there should be a small space between groups.

If the bog garden is planted near a pond that overflows or a stream it may not be necessary to constantly keep the ground moist. If watering is required, one possibility is a soaker hose buried about three inches in the bog and about two feet apart. One of the beauties of a bog garden is its low maintenance, but if desired, the garden can be hand watered, usually about every five days.

Learning how to make and plant a bog garden correctly is not difficult and the rewards are many. It will result in a fantastic, diverse display of plants and flowers that are much needed by our native amphibians as natural wildlife habitats are continually being lost. It is also a good source for cut flowers and a wonderful habitat for many other animals and insects like birds, butterflies, newts and dragonflys.

Small marginal plants look good at the front, with perhaps a lilly and some oxygenating plants deeper under the water, floating pond plants can also be a nice addition but are generally hard to overwinter and are best treated as annuals. If you are looking to stock up on koi pond plants you will have to take a different tack and make allowances for the sheer size these fishes can attain and their voracious appetites for everything leafy!

Bog Plants

These are the plants that really love soggy damp conditions but don’t like their feet totally immersed as marginals do. They do best in a purpose built bog garden at the side of the pond. Hostas, Primulas, Gunneras and Lobelias are a good place to start looking. Always take into account the indicated eventual size on the plants labels and lay them out in their pots so you can space them pleasingly before planting. They grow very quickly , so though an area may look spartan at first, if you do overcrowd your plants it will look very messy when grown.

Marginal Plants

They are generally planted in plastic crates or pond baskets, lined with hessian and filled with special loam based pond plant compost. They are then topped off with a good 1” of large pea gravel to stop fish from disturbing the soil. Place on the marginal shelves around your pond. You can mix and match irises, rushes and grasses at the back and sides with marsh marigolds and forget-me-nots at the front. So many too choose from!

Oxygenating Plants

Water Lillys

Everyone is familiar with the beauty of the water lily. Not always the easiest plant too grow in the past, it is now getting easier due to much more rigorous varietys being produced. There are now very many hardy water lilies to choose from in an array of colours and petal shapes. Some get huge and some are perfect even for small garden ponds, I strongly advise you check size before you buy! Also I would recommend investing in a good quality pond plant fertilizer, as they are hungry plants and will fade quickly if undernourished. When transplanting to a larger basket make sure the tuber is at the same depth to help avoid crown rot.