Erosion control plants on a slope | Page 2 | Construction and DIY projects | Forums

KVR said
how long does it take for those to establish themselves?

She suggested that they be planted in spring or fall. Even winter she said would be okay, just not in summer. Spring and fall, about a season (3 months). Winter she said they would be dormant but would send out roots. Likely 3 to 6 months. She said the Iris would take the longest to establish. The others establish rather quickly which is part of why they are chosen.

She suggested digging the depth of the root ball and twice that around, then to fill the void with semi loose packed dark organic soil to help give the plants a chance to start.

Since the stream is seasonal, sometimes flowing and at differing depths, and sometimes bone dry, that both the typha and iris would be hearty enough to handle periods of partial immersion mixed with periods of relative drought.

All are hearty and aggressive growers, but not so overly aggressive as to be invasive. And all are little to no maintenance. All are suited to my local zone 7 climate, and to partial sun and shade. The iris likes more sun, but would be alright.

I also asked about planting on the inlet side mixed in with the riprap (midsized rock for erosion control). She said as long as I do not trim the root balls and plant in void space between the rocks filling with organic soil, that the root systems should have a good chance of reaching down into the fill soil below.