Hello Tracey,

An auger is not recommended as it might worsen the situation, creating smooth-sided planting holes that roots will have a hard time breaking through. Organic matter, usually in the form of compost, is the best soil amendment to combat and resist compaction. It can be mixed-in prior to planting, though this can temporarily damage soil structure (and harm roots already in the area), or added as a top-dressing after planting, which earthworms, soil-dwelling insects, and other organisms will gently and gradually "till"-in for you naturally. If you use a biodegradable mulch over the area between plants, like wood chips, bark mulch, or leaf litter, that will compost in-place over time and continue to add organic matter to the soil below as well.

The cardboard box technique you describe is not recommended because it will create several problems for the new plants and the roots already there. (Are these roots from an undesirable plant, or something you want to keep healthy, like a nearby tree or large shrub? That will impact how we suggest you proceed.)

The easiest approach to planting will be to either sow seed or install plugs. Seed can be challenging in that it is intolerant of drying out while in the midst of germination, but it is a cheap option for many plant species and they can be started in containers before being moved into the ground. This will help minimize the other challenge of distinguishing germinating seed of the desired plants from germinating weeds, both of which might look quite different and not very recognizable when that young compared to their more mature forms.

Plugs are young plants already started from seeds or cuttings that are older than seedlings but smaller than the plant sizes typically sold at nurseries. They are easy to plant, having fairly small root masses (often just a couple inches wide and maybe four inches deep), and they establish quickly. The trade-off is that not all species will be available as plugs, but if you were using native plants, their rise in popularity means that plugs are rapidly becoming more available, either at local garden centers or online from native specialty nurseries. You'll mainly find perennial plants offered as plugs or seed; annuals tend to be mainly available as seeds, though cottage garden-style plantings tend to use mostly perennials anyway, and while Maryland does have native annuals, they are not well-known or widely-grown yet.

Miri

Hello Tracey,

Mitigation of soil compaction takes time, and is a gradual process. Using a barrier like newspaper underneath mulch can hamper its benefits of adding organic matter, since the newspaper takes a while to biodegrade (if it breaks down quickly, then it's not a great weed barrier) and it blocks access to some of the organisms that would start to break down the mulch. Newspaper might also interfere with how well the soil underneath that layer receives moisture from rain or irrigation.

Do you happen to know the identity of the plants whose roots are infiltrating the site(s)? That will help us understand the nature of the problem, as ideally that plant should be removed before planting if it's unwanted and causing recurring problems with root invasion. We can suggest removal options once we can ID it and get a sense of the setting. Can you share a photo or two of the planting site?

We do not recommend removal and replacement of soil. Not only will the current root problem reoccur if they keep growing into that area, but using two different soil types next to one another can lead to root health problems as soil drainage and nutrient retention will differ between them. Unless there is a contaminant that cannot be removed (lots of heavy metals, for example), the soil only needs to be amended, not switched out.

Once we can see the situation, we'll have a better understanding of the challenges it presents so we can offer some more specific options for fixing the problem.

Miri

Thank you for the photos. If any wiring for the lamp post is not in that area (though it's probably deep enough anyway), then roto-tilling would be the most straightforward way to loosen the soil and mix-in any amendments like compost. While normally we discourage tilling because it can damage soil structure (which will take time to recover), in this case it's probably the most efficient approach to remediating the area since any roots it cuts apart in the process can be sacrificed since you don't want them preserved. A broadfork would help loosen the soil as an alternative, but as a manual tool, requires more effort. (To be fair, some rototillers can be hard to wrangle or steer in small areas, depending on how deeply they till.)

If the current vegetation is all weeds (or at least unwanted plants), remove that growth first, by mowing/cutting it down and digging out what you can, since it will make working the soil afterwards much easier. If stubborn weeds, like any aggressive shrubs or vines, resprout, then consider treating the regrowth with a systemic herbicide to kill the roots before another attempt at removal. (That would not make the bed unsuitable for planting.)

Miri

Hello!

 

I hope the summer went well.  I am replying to a closed topic but am hoping to get some more help.

 

The soil in this yard is very compacted.  Water does not drain easily and I am hoping to prepare it for a garden next Spring.  I have a plan and would like your advice on it.

 

1. Buy bags of Leafgro compost, manure (from poultry) and Bloom Bulk Woody Blend at the end of August.
2. Place bags over the part of the yard I am hoping to amend. I’m hoping this will slowly kill the weeds that are below the bags as rain and the weight of the bags compress the plants.
3. At the end of February, on a warmish day, I will loosen and aerate the area with a garden fork.
4. I will mix the bags in 1 above with the soil leaving dead leaves collected in the Fall over the mix.

 

I’m hoping that will add enough organic matter to start to make a difference in the soil.

 

Please let me know your thoughts.

 

Thank you so much!

 

Tracey

 

Hello Tracey,

One compost product (Leafgro or Bloom, whichever you prefer) should be plenty, as you don't need both plus poultry manure. While the bags themselves might help to smother some weeds, they might not be as practical to use for that as a sheet of landscape fabric or tarp. (Landscape fabric, since it allows water to seep through the material, would be preferable to a plastic tarp. There are biodegradable versions of paper-based "landscape fabric" that would be a more sustainable option if you prefer, and it can be left to degrade on its own instead of having to be removed when you're ready to plant.)

When ready to mix it in, incorporate the compost to a 4- or 6-inch depth so it is well-blended with the existing soil. Compost will help to resist compaction and improve drainage, though if the area still tends to stay damp, you can either select plant species tolerant of wetter soils or build a raised bed that gives a planting bed several more inches of height so it drains well.

Miri