Heavy shade, shallow soil, subject to freezing. Ideas?

[comarley]

I'm looking for ideas for a container at a small mixed-use building. It is a permanent fixture outside, so it's subject to freezing and can't be brought in when it freezes. It sits above the basement, so it is lined with a pond liner and has a couple inches of stone at the bottom for drainage (above the liner). It is part of a covered entryway, so it gets no direct sunlight. Here are some more details:

• Heavy shade
• Soil depth = 2-3" in most places; 7" in others
• Roughly 75 square feet
• Zone 6b or 7a

I'm looking for something that would stay green year-round (if possible) that wouldn't require a lot of water once established.

I talked to a local nursery, and they only came up with Creeping Jenny. I'm fine with that, if that's the only option, but I was hoping for some variety.

Where the soil is the deepest (7"), there is a glass display window behind that, so I wouldn't want anything taller than 12" there. Beside the window there is a solid wall, so something could be trellised there.

I'd prefer something that flowers, but it's not necessary. The top priority is green throughout winter so I don't have a dead patch at the front of the building.

Any suggestions?

[rainbowgardener]

Wow! Very challenging!

All those things you put in the title, heavy shade, shallow soil, subject to freezing make a tough growing environment. But then add in the pond liner and it is kind of a disaster. I take it this very large planting box (4 by 20 ish ?) is outside, where it gets rained on? It will fill up like a bath tub and everything will drown. Hmm, you said that it is part of a covered entry way. Does that mean it does not get rain? That is a help for the water issue, but you still have to water the plants.

People always used to put gravel (broken up pots, small rock, etc) in the bottom of flower pots, thinking it would aid in drainage. It does NOT. And especially where you have so little room for soil to start with, the rock just takes up space that could be soil. Water does not cross the dividing line between the soil and the rock until the soil is completely saturated. Please do read this short article about stone in the containers as a garden myth and why: https://www.todayshomeowner.com/garden-m ... ontainers/

I think you will need to look for bog plants, things that can tolerate standing water or saturated soil, like: lobelia/ cardinal flower, bog bean, marsh marigold, obedient plant, white pickerel flower, milkweed/ butterfly flower, thalia. None of those are evergreen. For something evergreen consider:

Atlantic white cedar (Chamaecyparis thyoides "Shiva") is a dwarf evergreen that thrives in a soggy spot and grows in U.S. Department of Agriculture plant hardiness zones 3 to 8. Light greenish silver needles turn to a bronze shade when cooler weather arrives, and small rounded cones develop in the spring

Consider the shrub variety inkberry (Ilex glabra), which grows in USDA hardiness zones 2 to 11, to 10 feet high and wide, with dark green leaves and black berries. Dwarf varieties are also available and are suitable for creating low hedges. Yaupon (Ilex vomiitoria) grows to 20 feet high and 15 feet wide and tolerates high alkaline soil. The dwarf variety grows to 5 feet high and wide and both grow in USDA hardiness zones 3 to 9.
https://homeguides.sfgate.com/evergreen- ... 28382.html

Here's an article from Penn State about trees, shrubs, groundcovers for your area that tolerate wet soil: https://extension.psu.edu/plants/gardeni ... -wet-sites
You would have to investigate them for which ones also tolerate shade.

Part sun is one thing, but deep shade is pretty killer. Of their list shade tolerant ones include sweetspire, button bush, summersweet, leucothoe, swamp azalea, lady's mantle, plumbago, bleeding heart, daylilies, hostas, pulmonaria/ lungwort, tiarella/ foam flower. The leucothoe is a very low growing broad leaf evergreen that might be worth your consideration.

But shade tolerant does not mean they would thrive with no sun. Given how many other challenges this area has, have you considered adding some artificial lighting to help your plants along?

[applestar]

I need to know the detail about whether it fills up with water, too. That's going to be a major factor. I was thinking, though, that if it does, you maybe able to put in a hose drain to send excess water out and bring it down to belw the top of the gravel layer....

On the other hand, if it HOLDS water and doesn't go dry, that would open up other possibilities like bog plants and water gardens. A fountain... If you trust this liner to not fail.

I would love to see a picture of this area -- or a rough sketch -- I'm having a very hard time imagining it.

Rainbowgardener, don't forget the "no taller than 12 inches" part -- it would have to be some kind of a deep shade/understory, bog tolerant, drought tolerant groundcover....

No sun at all? Maybe some kind of a fern might work... Oh but that wouldn't be evergreen....

The color of the wall and ceiling of the covered area could affect the light level. You could arrange refurbished yard sale/garage sale mirrors on the wall, for instance... Or paint the entire area white.

Winter hardiness... I'm thinking zone 6b or the location might be protected enough to have a solid microclimate of zone 7?

[rainbowgardener]

the no taller than 12" was only for part of the area, with the window behind it.

But yes, a couple of pictures would be very helpful!!

[comarley]

Hi, thanks for your response.

Since it is part of a covered entryway, it does not get rain. I should've been more clear, sorry.

All water it gets will be brought in by hand (until I become too annoyed with that and run some sort of drip line out there).

I plan to put in some LED lights above the plants, but the lights will be 8' above them; will it help from that distance?

I'll go down and take some pics and post them in a few.

[comarley]

The brick on each side of the photo is part of the front of the building, so the planted area starts at least 10' inside the building footprint. The building faces NE.

The lowered ceiling is about 8' from the dirt. The dirt right in front of the display windows is where it is 7" deep. Each of those areas is about 4' wide x 2.5' front-to-back.

In regards to lighting, the perimeter of the lowered ceiling matches the perimeter of the planted area. There were some old lighting fixtures there, so we were going to replace them with recessed LED lights. Are there bulbs that would make a difference from that distance (that aren't insanely expensive)?

[applestar]

OK, so it's a commercial not residential area. No wonder I wouldn't picture it.

...maybe it's because I was just thinking this looks do-able this summer, but I SO want to put an urn and basin fountain in front of that wall. I was thinking of trying to make one of these:

https://www.lowes.com/creative-ideas/gar ... in/project

For the recessed light sockets,maybe one of those really big CFL/fluorescent spiral bulbs? I got a couple of bulbs that fits a regular light bulb socket and put it on a torchere as supplemental light for some plants. Look for them on photography supply websites (but you can get them through Amazon). The ones I got are biggest/brightest that still fits regular sockets, but there are bigger/brighter sizes. I think they are used for warehouses, barns, etc. commercial building overhead lights... I might have seen them up near the ceiling in grocery stores, too. But Photography supply sells the 6500K full spectrum/true daylight color spectrum ones that are good for growing plants.

You also have the option of putting bright fluorescent/shop lights near the bottom of those windows on the INSIDE to shine OUT to light up the beds if you wanted to/if you can do so. Maybe hidden inside window bench-like structures/boxes that are open to the window-side.

[rainbowgardener]

It's kind of a crazy idea to try to grow plants there , but we like going for crazy challenges!

So thoughts: Is there any reason you can't build the sides of your box up one more board higher? Given all the other stuff going on, I think making it a bit deeper would really help with having more soil/nutrients, ability for roots to go deeper, a little more protection from freezing, better drainage, etc.

Lights in the ceiling will help some. But light intensity varies by the square of the distance. So if the lights are 8' up and you can bring them down to 4', your plants will get 4 times the light intensity. If you can bring them down to 2', your plants will get 16 times the light intensity. So I agree with applestar, really you need to find some ways to get the lights down where the plants are. Could you put some fluorescent tube lights along the box sides with reflectors and angled in so the light is aimed at the plants?

[comarley]

Ok, thanks for the lighting ideas! I'll have to look into what's do-able.
Any suggestions on what to plant there?

[Susan W]

Simple question, perhaps. Was this planter there before? What was in it?
Check with your garden center for English ivy. Not a fave for outer spaces as it can like itself, but perhaps a good choice for a contained space. If the deeper part can handle tall (not block window), check out horsetail. It will grow anywhere.

[comarley]

There were no plants there. It was a display window that was broken, so it was removed (and the windows that are in the photos were installed at the back of the area).

[applestar]

This is turning into a "Chicken or the Egg?" question.
As it is, your choices are very limited. If modified with more lights, more options.

So it's hard to make suggestions without knowing how much improvement you are willing to consider and how much you can commit to.

[imafan26]

That is hard. I don't know what would tolerate freezing but
ferns, heuchera, ivy, pothos, hosta, begonia, impatiens, and vinca can tolerate fairly deep shade but may not bloom much without good light or supplemental lighting.

[comarley]

Well, I can live without blooming. Blooming would just be a bonus.