How to make a bog garden

A bog garden can also be an attractive feature by itself, without a pool. It may be the only choice to occupy an area where water collects to form a natural bog. Here's some pointers on how to grow a successful bog garden.

As both drought and excess water can be harmful to the various plants that prosper in a bog garden, it may take considerable attention to maintain a precise balance of moisture during wet or dry spells.

Sufficient water is usually present in heavy clay soil. It can be conserved by a topdressing of composted leaves in mid to late spring. If the bog garden is in a low-lying area, however, there is danger that the plants will be totally submerged during periods of heavy rainfall. To successfully grow bog plants where soil drains well, it may be necessary to construct a special garden bed that will retain water, while allowing excess to escape.

Most bog plants are herbaceous perennials.

• The best time to plant them is in early fall, while the soil is still warm from the summer.
• Make the planting holes wide enough to allow for the roots to be fully spread out. Make the soil finger firm around the roots; if it is wet, however, take care not to compact it too much.
• Do not space the plants far apart. Groups of plants of the same type are more striking than the same number of plants dotted about at wide intervals.
• Where the soil is moist and rich, many bog plants, such as primroses and irises, will add to this cluster effect by self-seeding to make drifts of blossoms in subsequent seasons.

Proper conditions for bog plants can be created.

1. Dig a hole 25 centimetres (10 inches) deep, the width and length you wish, and put three centimetres (one inch) of sand on the bottom.
2. Line the hole with heavy-duty plastic sheeting.
3. Cut holes in the plastic liner all around the sides, about 15 centimetres (six inches) up, to drain surplus water.
4. Cover the base of the sheeting with a layer of sod, laid grass side down.
5. Finally, overfill the hole with about 25 centimetres (10 inches) of garden soil, mixed with an equal amount of leaf mould, to make a raised soil bed. The plastic liner will hold water, and the sod will provide nutrition as it decomposes.

• Make sure the soil in your bog garden remains damp at all times.
• This may require frequent watering in dry weather. If the bog garden is located downhill from a pool, you can flood it by allowing the pool to overflow as needed.
• Or you can install a pool-side sprinkler system, which will help aerate the pool as well as keep the bog garden moist.
• In fall, cut the dead foliage of herbaceous perennials down to the ground and clean up the debris. Then apply three to five centimetres (one to two inches) of well-rotted compost or leaf mould mixed with dehydrated cow manure.
• On top of this apply three to five centimetres (one to two inches) of shredded leaves or bark. This will nourish the soil and help it retain moisture the following year.