I thought I'd publish this article we wrote last year again. When trying to get some of the bog plants started in your ponds its best to start them out slowly in the water, since most of them are swamp like plants. They can tolerate a few inches above their pot once they are established and growing. When growing them in our greenhouses we have them growing in two inch net pots in bins that have about one inch of water in them so the water is keeping their roots wet.
Here's the article.
I've been wanting to write something on this subject for some time now. Finally, I have a bit of time to address the subject of water depth for bog plants and marginal plants. Simply put, bog plants like their "feet" wet. Translation....roots and soil moist at all times. When the plants are first planted, this is especially important. Many of the bog plants will take deeper water as they mature and spread. But, when you first receive your bog plants, you will have better success if you place them where there is no more than a half inch or less of water above the soil line. Think of the marshes and swampy areas, you have passed while traveling down the road. These natural reservoirs, fill during the rainy season and will dry out during dry spells. The plants adjust to the varying water depth and grow and spread rapidly. If you have a question on a particular plant, just ask and we will be happy to help you plant and grow beautiful marginal and bog plants.