Pitmoss Follow-Up

Back in September, I posted about my experiences with Pittmoss. I thought I should post an update now that a few months have gone by.

First off, the plants that I used the Pittmoss with seem to be doing quite well. Of course, I don’t really have a control, and most of these plants (except the Yarrow) came from the same source (The Growers Exchange). In particular, the greek oregano, sage, and thyme (lemon and french) are doing quite well. I would at the very least recommend the Growers Exchange. (One friend did get some tarragon from them that didn’t do well, but their other plants seem to have been fine.)

Clockwise from top left, the square bed contains rosemary Hardy Hill, Lemon and French thyme, Yarrow Richard Nelson, and culinary sage. The rectangular container at the bottom contains Greek oregano.

Now, for the not-so-good news: In some of my containers, the Pittmoss has compressed a lot. I’d say it’s reduced by a third to a half. I was expecting some compression, given how fluffy the Pittmoss is, but this is more than expected.

I am still planning to use Pittmoss in most of my spring planting. However, I may try to set up some beds and pots with it ahead of time and then let it sit a bit before planting/transplanting. I also want to try to add some growing medium to the Russian sage and amsonia, where the Pittmoss has compressed the most. 

As an aside, the pictures in this post were all taken in January. We just had a big snowstorm, so the sage and the other herbs are looking less green, but… Well, my garden was very confused about the seasons for a while. I’m blaming it on global weirding.

Pittmoss Review

3 x 3 raised garden bed with Pittmoss mixed into the soil that was previously in the bed. Clockwise from the top left, the plants in this are culinary sage, rosemary Hardy Hill, lemon thyme, and French thyme.

This post is to document my experiences (to date) with a new-to-me planting/potting medium called Pittmoss. Before I get into details, I should state up front that I purchased the Pittmoss and all of the plants I’ll be talking about, and there are no affiliate links in this post.

To be honest, my decision to try it really came down to the fact that, while the cost per cubic foot of the Pittmoss was relatively high, shipping costs for my other choices would have been prohibitively expensive, and I was really looking for something that would just show up on my doorstep. (I’m lazy, remember?)

I’m not sure where I first heard about Pittmoss, but it’s basically made from recycled paper with other stuff (eg, bark, compost, microorganisms from bovine compost, etc) added to it. I was interested initially because it’s peat-free, but then also because it uses recycled paper. (Their website says upcycled.) I believe it’s called Pittmoss as a play on peat and because the company is based in the Pittsburgh area.

I ordered several 2-cubic-foot bags of the stuff, and they arrived at my doorstep, as expected. They were packed in cardboard boxes, which I stacked up. Leo decided that the stack was his new perch and he greatly enjoyed lounging there for a few days until my fall plants arrived.

Amsonia Blue Ice.

The Pittmoss smells… essentially like what it is: old paper. It’s a bit musty but the smell doesn’t bother me. If you’re into that old paper smell, you may even enjoy it.

Once my fall plants arrived, I took them and the Pittmoss to the patio to begin planting. I have to say, Pittmoss is very lightweight. Usually, carrying 2 cubic feet of potting medium would have meant I need a break. (I’m not very strong. It’s probably related to my laziness.) But carrying 2 or even 4 cubic feet of Pittmoss is no big deal.

Once you open up the bag, it looks a bit like gray insulation. The texture is super fluffy. There were a few chunks of paper still stuck together. When you break them apart, you can see all the colorful bits of shredded paper. It’s a little like breaking up an owl pellet, I suppose. (I’ve never done that personally, just seen it done.)

Russian sage.

I used a bit over 2 cubic feet to top up my raised bed and mixed it in with the existing soil in the bed. I used about another cubic foot mixed with existing soil to fill 2 large round containers, a 1’x2’ rectangular container, and a window box.

The raised bed got sage, rosemary, and 2 types of thyme and will also be getting some yarrow later. The rectangular planter got oregano, the window box got chives, and the two round containers got russian sage and amsonia blue ice.

Oregano in a rectangular planter. The Pitmoss looks like gray fluff/mush here.

Pittmoss claims to have “improved water retention” and to require ⅔ less watering. I’m assuming this is compared to peat-based planting media. I’ve planted a whole variety of plants in this stuff, and their water needs range from ‘really liking dry’ to ‘really liking wet.’ I’m really curious how they do with the Pittmoss. My suspicion is the rosemary will be the least happy, but we’ll see.

I’m also curious about how much this stuff will compact, given how fluffy it started out. I don’t want my plant roots trapped in paper mache. Similarly, I’m curious how this will hold up over time, as everything I’ve planted in it so far is a perennial. I may just try some basil indoors to see how it does with an annual. (The basil on the patio has become a tasty snack for something that owes me a few bucks for seed and watering.)

So here’s a bullet point summary, if you didn’t read the above.

  • Good:
    • lightweight and easy to carry
    • fluffy texture is kind of neat
  • Neutral (for me):
    • smells like old paper
  • To be determined:
    • how much it compresses over time
    • how it does for perennials
    • how different plants like the water retention

It should also be noted that this is a purely observational, uncontrolled, non-blinded experiment. It has no scientific validity, but it’s fun. I’ll post updates.

Gardening with Cats

When I’m in the garden, the cats are usually with me. They seem to enjoy being out in the fresh air,* and Leo especially enjoys chomping on plants.

Garden cat with echinacea.

This has meant that I’ve had to modify my plant selection in order to keep them safe. A remarkable number of plants are toxic to cats, including:

  • Daffodils, hyacinths, tulips, lilies, and irises
  • Peonies
  • Garlic, onions, shallots, leeks, scallions, and chives
  • Parts of the tomato plant
  • Hydrangeas, azaleas, and rhododendrons
  • Foxgloves, lupines, and monkshood
  • Morning glories

I don’t grow any of the plants listed above, and I usually spend a good bit of time checking if a plant I’m interested in is reasonably cat safe.

I say reasonably because some plants are more toxic than others. Most of the ones listed above are pretty bad for cats, and can even kill them.

I do, however, grow some plants that could have some mild effects, such as mint and rosemary. Even catnip can be dangerous in large quantities. In addition, some cats, like Leo, will inevitably throw up the plants that they eat onto the carpet. (That seems to be part of the fun for them.)

For other plants, I make concessions about location: Hostas are also toxic to cats, so I only grow them in front of the house, where the cats are not allowed to go. Eventually, I may grow some other shade-loving plants that aren’t cat friendly, such as hellebores (lenten roses) and dicentra (bleeding hearts) out front as well.

The big exception to all this is snake plants. They’re toxic, but I have some in the house because Leo shows no interest in them and they do well in low light.

At some point, if I can figure out a way to keep them out of the cats’ reach, I may try growing chives and other, less cat-friendly people food.

If you’re thinking of growing a plant, I recommend first checking out the ASPCA’s lists of toxic and non-toxic plants. It’s not a complete list, but it’s the most comprehensive one I’ve found.§

If you just want some suggestions for getting started, though, I recommend snapdragons, petunias, alyssum, pansies and violas, cornflowers, and cosmos for ornamentals. For edibles, chard, beets, lettuce, the broccoli and cabbage family, cucumbers, and most squash seem pretty safe.

Some beans do contain toxins that break down when cooked, but most are fine to grow around cats. You should probably avoid castor beans, though. Hyacinth beans are fine to grow, but can be tricky to cook properly.

Finally, if you’re not familiar with sweet peas, they aren’t edible and are toxic to animals and people. Edible peas (ie, garden peas, English peas, snow peas, and snap peas) still often have pretty flowers, though.

*Or what passes for fresh air in the city.
Grape hyacinths are a different species and are listed as cat-safe by the ASPCA.
These are often featured in cosy/country mysteries.
§Sometimes, a plant isn’t on either the toxic or nontoxic list, and you have to decide if you’re going to risk it.