Bog beds can work quite well, if you know what to expect
Otherwise, you can run into two main bugaboos that will spoil it... and a third one that might creep up on you
~Bog beds are difficult to weed, they tend to explode with all sorts of the worst grass weeds from seed...
~ Bog beds lose water at a very fast rate, it can be tricky to provide stable moist conditions
~The third bugaboo that tends to sneak in, badly drained saturated soil tends to go 'off' and acidic inches down, plant roots spoil
There is one 'obvious' way to do a bog bed, and that is to use a liner with a hole or two most of the way down to stop the soil in the liner from being saturated, it 'lets' excess water out. Downside, water evaporation rates very high. In a sunny position it will struggle with drying out...
The less obvious way to do a bog bed is to make a pond as per usual, and plant the bog plants in containers with the soil level a few inches above the water level. this works well, as it becomes easy to keep weeded, and water loss from evaporation is much lower... Soil has a much bigger surface area than water, so, the 'soil' surface tends to lose water twenty? fifty? times faster than water....
Be a little wary of what plants you use in a bog. A lot of very attractive plants are missold to zones too hot for them.... Gunnera, Marsh Marigold, Mare's tail come to mind as very elegant in the water garden books and garden centre shelves, to die like flies when 90°f heat whups them
Regards, andy
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