I have 12 sweet viburnums (Viburnum odortatissimum) in a row as a future privacy hedge. I had to replace 2 of them just recently because they suffocated from sitting water when I had heavy rain at the end of the fall. They all discolored but only 2 died, thankfully. So basically, this whole strip of land these viburnums are planted on has poor drainage when it rains a lot and I'm wondering the best and cheapest way to add some drainage when there are already plants there? I know they'll be a bit stronger as they mature, and possibly survive the suffocation, but not necessarily, and I don't want to take the chance. I'd hate to see them die off after maturing should a drenching rain leave water sitting for a month.
You need somewhere for the water to go. If there is anywhere close by that is lower than the planting area then:
- dig a trench to the lower area about six inches wide and at least six to twelve inches deep.
- Place four inch perforated drain pipe with sleeve in the trench
- backfill the first four inches with gravel
- Optional -place a layer of landscaping fabric on top of the gravel
- backfill to ground level with soil
Or construct a french drain. I find a sturdy plastic bucket with the bottom removed works well. Line with gravel, top with landscape fabric and soil and you are done.