Front Porch Bed - A Look At Soil Conditions - March 2023

The planting bed that is out front of our porch has been something that has been on my mind for years.  Specifically...the growing conditions.  Between a few things going on out there, I think it might be time (this year) to take an even more aggressive stance at improving the soil across this foundation planting bed.  Last year (2022), one of the items on my annual to-do list was to think about how we improve the conditions up there and I suppose that I did that (a little) and gave myself a partial grade of complete.  

The way I was thinking about this problem was across a couple of fronts:  hydrophobic mulch and the root mat from the Norway Maple.  

Starting last Spring, I went about trying to fix the hydrophobic mulch issue - including the addition of some nitrogen in the form of alfalfa cubes and raked it in.  Then, in the Fall, I attempted to do even more.  First...with the removal and grinding of the Norway Maple tree, I'm hoping that the root mat issue continues to recede.  But, I also added a bunch of organic material to the area.  First, by spreading the backyard compost that our pile was able to create.  Then..with a load of composted manure and mushroom compost.  10 bags of manure, 4 bags of compost.  I also threw on a few loads (5 gallons at a time of biosolids around the hydrangeas. 

I'm certain that the addition of that organic material is going to help - especially as a balance to the high quantity of wood chips that the stump grinding created.  

(also...I've been planting annuals out there as a way to naturally improve the soil, of course.)

But, when I was out there this past weekend, I noticed that the area was heavy.  Wet and heavy.  And, based on planting annuals out here the past five-plus seasons, I know that I'm dealing with clay soil.  This is an area of foundation backfill that our builder did after our foundation was poured.   

And it is similar to the other parts of our property that have a thin, layer of top soil on top of a deep layer of clay.  I've come to learn about the concept of a 'clay bowl' - where water has a hard time of moving through the clay layer and ends up sitting in the root zone.  Some call it the Bathtub Effect.  I've seen this first on the 3" Chanticleer Pear flowering tree that our builder put in IB2DWs.   We lost a tree and were about to lose the second one before I got busy trying to figure out what was going on.  The solution that I came up with?  Dig a deep hole with my post-hole digger in a low spot.  To sort of serve as a vertical drain to let the water pass out of the clay later.  

Ever since that first, (somewhat successful) deep-hole digging, I've followed that approach when planting other things in heavy clay.  First with the planting of the tiny Bald Cypress.  I dug down almost 24" deep to find the bottom of the clay layer there.  In that spot, I filled with a mix of gravel and soil.  It seems to have worked.  I also did the same thing with the small Saratoga Ginko that I planted last year.  Deep hole first, then plant on top of it as a sort-of release valve for any excess water.  

Which brings me to these front yard beds.  I've posted about a few 'Priority Areas' for 2023 this year already including the feet of the Lindens and the IB2DWs extended area.  The most critical 'priority area' for this year is this front porch bed.  I haven't posted about it yet, because I'm still exploring solutions.  

But, before I plant anything, I think it might be worth the effort to try to work on the soil conditions. 

How am I going to do that?  My thinking is a mix of those deep holes and organic material.

I piloted this thinking by pulling out the post hole digger to see what we're dealing with out there.  Below, is a photo showing a hole that I dug.  Mulch on top, root layer, some top soil.  Followed by clay all the way down.  I got to the point where I was reaching medium-sized gravel pieces.  This hole is in front of the current boxwoods down close to the border where the bed meets the turf.

I took a couple of small limbs that were laying around out front from cleaning up the bottom of our Christmas tree and stuffed those in the bottom.  I figured, they'd provide some air holes down there.  Then, I took some of those biosolids that I have been putting on the yard and dumped them in - filling up the hole 3/4 of the way.  I pushed some of the mix of clay, mulch and top soil back on top.  Capping the hole.

I'm going to try to find the time to dig out a dozen or so of these deep holes.  Six or so across the front.  And six or so back by the Hydrangeas/where the Norway Maple was.  First...as a way of making sure we remove the 'bathtub effect' with clay soil.  And....then....Filling each of them with some biosolids as a way to improve the soil in these vertical silos of sort.

There are studies on doing something similar - some call it 'Vertical Mulching' on trees.   That's the sort of approach that I think can't possibly hurt here, right?  A dozen eight-inch-diameter holes, 18" or so deep filled with the municipal-sourced biosolids material that I use for topdressing.  Seems like a project worth tackling before planting of new material out front. 

Something that will have to go on my 2023 to-do list:  improve conditions out front with mix of techniques.