Landscaping Sand Mound

[Schieftain]

Hi All,

I have some questions about landscaping around a sand mound.

We live in Central-PA and bought a house with a sand-mound in the back-yard about 9 years ago. Original owners had landscaped the front of the sand-mound (which faces the house). Planted various bushes and three pines. Two of the pines were Red Pines, not sure what the third is (has long needles).

Over the last few years, we planted some weigelas and lilacs in this same area, not knowing this was a big no-no.

The pines are planted about half-way down the side of the mound, on the front (end) of the mound. I have read that some trees can be planted on the toe of a sand-mound. But have also read that trees should be kept at least 20' away from a sand-mound. Should these trees be removed? Mound and trees have been in place for about 15 years.

Second question is re. the bushes. Are Weigelas and Lilacs known to have aggressive root systems? These are planted closer to the top of the mound, also at the front end. Would they be okay if we moved them further down on the slope? I really want to avoid a costly problem with the mound.

Thanks.

[applestar]

Why is there a sand mound? How deep is the sand? Can you level it down somewhat?
What is the rest of the soil around the garden like? Would incorporating some of the sand be beneficial?

I live just outside of the NJ Pine Barrens where native plants live in deep sand but the ground has a somewhat high water table. I was told by the caretaker of a native Pinebarrens species garden that I could pseudo-duplicate the conditions by building a 24" deep raised bed over my garden's clay subsoil and filling the box with sand.

Plants that grow well or reasonably well at the beach may do well on some parts of your sand mound.

[rainbowgardener]

I'm not understanding what the concern with the weigela and lilac and "aggressive root systems" is. What kind of costly damage are you trying to avoid? What could happen?

I have a weigela and a lilac in my front yard. The lilac was probably planted when the house was new, closing in on a hundred years ago. It is huge and takes up much of one half of the front yard. The weigela I planted, so it is pretty small. But both of them just sit there and get bigger as allowed. Neither of them spreads anywhere else or does any damage. But of course, I have heavy clay soil, so I can't say it is the same.

[Schieftain]

A sand-mound is a type of septic system common in many rural areas nowadays where the soil does not "perc" enough for a traditional septic system.

The concern about root systems is that fast-growing and water-loving plants will send roots out faster/farther and can destroy the septic drain-pipes. You then have a massive bill to tear up and re-build the septic system.



I took down the trees and one gigantic bush last night. Now I have the weigelas and lilacs to move.

I know lilacs have a fairly aggressive root system, and I will be moving those far from the mound.

Anybody know about weigelas? How aggressive their roots are? If they don't go too far searching for water, I could just move them to the bottom of the slope. I can't find anything online that talks about their roots though.

[rainbowgardener]

OK sorry I had no idea we were talking about a septic system. Weigela does have an extensive root system -- deep and wide.