Vegetable Garden: Understanding Soil

Day 9 of Garden Tribes’ Boot Camp for novice gardens. Today it’s all about soil–what it is, what it isn’t, and how you make it work for you and your harvest. Before going any further you should know that if you are in a newly constructed house, the “material” surrounding the house may bear little resemblance to soil. Between the time the old house (or whatever) was removed and you moved into the new house, most of the site was probably changed significantly. You may even have the joy of finding MaDonald’s wrappers when you stick a shovel in the ground, or pieces of concrete, or great rocks that had to be either buried or disposed of some other way. So what is said about “soil” here may not actually relate to your situation. I suggest you dig a few good big holes in various not-too-conspicuous places to determine what is down there.

As the expression goes, “Feed the soil, not the plants”.

  1. Soil is a complex structure of organic and inorganic things. The quality of soil is dependent on the size of the particles, the amount of air space around the particles, and the percentage of organic matter mixed in among the particles.
    1. Clay is the smallest particle of soil. The more clay, the denser the product, the less air space, the wetter, the heavier it is. But clay is wonderfully full of all the macro- and micro-nutrients and trace minerals needed for most plant growth, and is generally slightly alkaline. More on pH later.
    2. Sandy soil is the opposite: large particles, it holds on to little nutrient, but drains very well. Sandy soil is considered “light”–because it’s not heavy, since it doesn’t hold much water.
    3. Silt is mid-sized particle, easier to work with, but still doesn’t hold many nutrients.
    4. Every ground space has some combination of the above three materials. And once some organic matter is added you have loam–either clay loam, silty loam, or sandy loam.
  2. In coastal BC because of our rainy climate, some of the nutrients that contribute to the pH of soil get washed out of the reach of plant roots. So in general we have acidic soil here, which is why rhodos, azaleas, heather, oregon grape, and huckleberry do so well and are found in almost every garden. If you have any of these, and they thrive, you can be fairly confident your pH is acid. That’s not a bad thing (don’t think sulphuric acid here), in that more nutrients are available to plants in an acid environment than in an alkaline environment. So acid is better than alkaline. And if your pH is really low, then you can grow better blueberries than I can!
    • Changing the pH of soil is pretty much a fool’s job. It takes several years of continual application of either a sulphur product (to acidify) or lime product (to alkalinize). Better to just appreciate what you have, and it you want to grow something that prefers a different pH, go with containers/raised beds. This is how many vegetables do well in acidic soil.
  3. The key to the good soil that you want to grow your plants in, is organic matter. Material that was once alive, when added to the soil, creates food for all the soil-based organisms that will increase the fertility of the soil. It’s those organisms that take the organic matter (last year’s banana peels and coffee grounds, or the sheep or mushroom manure, or Sea Soil…) and work on it to release the macronutrients (Nitrogen-Phosphorus-Potassium–NPK) and micro-nutrients (Mg, Ca, Fe, etc) that your plants need to grow and fruit.
  4. So the last thing you want to do is destroy the community of organisms that are doing the work of providing nutrition to your plants. You want to maintain the soil structure–not too much vigorous tilling, and certainly not every year. You want to avoid synthetic fast release fertilizers which can act almost like antibiotics against your beneficial bugs. And you want to continue to nurture them by giving them a supply of organic material ever year.

Here’s a crappy little video on feeling the quality of soil, and the post that goes with it: the handful of soil sort of sticks together, so it has a little clay, is obviously not that heavy, and not very wet, and doesn’t have much organic matter–it looks pretty grey.

Advertisements

Sheet Mulching, or not, or how to save yourself a lot of work

Autumn is a great time to plan and begin to develop new garden beds for next year– as though you didn’t have enough to do.

Sheet Mulching, or not, or how to save yourself a lot of work

Sheet mulching is the process of layering lots of different compostable materials OVER your grass in order to create a new planting bed without digging up and discarding the turf. And it starts with a heavy layer of newspaper or cardboard (or compost then cardboard, depending on your information source). Then there’s a few inches (more) of home-made or bagged compost or composted manure, then a lot of layers of straw (NOT HAY), leaves (preferably chopped/mowed), yard debris (not with weeds or any leaf diseases like black spot), manure (if you have it and if you can stand it), grass clippings (presuming you don’t already have a mulching mower). To a total of around 18-20″ above the original ground level.

Linda Chalker Scott is of the opinion that the layer of paper-product is counter-productive because it prevents/hinders air getting down into the area that you want to compost–the grass turf. She recommends just covering the area to be transformed with 12″ of woodchip mulch.

I’ve tried the sheet mulching thing many times with varying success rates–not least because I don’t have easy access to leaves (almost exclusively conifer neighbourhood), straw, manure, or grass clippings (mine stay on the lawn where they belong). And the racoons love to dig around it,DSCN1426 exposing the cardboard to air, and allowing it to dry out. So in general it’s taken two years to turn a grassy area into a planting bed for flowers or vegetables. Not very efficient, but at least I didn’t have to figure out how to dispose of sod (that can’t go into the yard-waste recycling bin).

DSCN0908

This bed (the area that looks darker and right down to the bottom of the picture) was sheet mulched last fall (2012) with cardboard and 3-4″ of city compost. You can see it was variably effective, with lots of grass and weeds growing through, and not enough composting-in-place of the existing turf.

This year I decided to try the wood chip mulch thing–not primarily to turn turf to planting beds, but because I wanted to add paths into the garden. You may remember seeing these pictures before…

The path is to the left, the right is currently potato bed and will be a shrub border in the fall.

The path is to the left, the right is currently potato bed and will be a shrub border in the fall.

I started in May by digging out the turf in the areas that were to be paths and spreading several inches of mulch. The clumps of turf were placed upside down in other turf areas that were to become planting beds of some kind. So in the picture above, to the left of the brick edging is the path, to the right of the brick edging is a layer of upside-down turf  topped with 6″ wood chip mulch.

...finally meeting up with the "translocated mountain of mulch"!

This mountain of wood chips was mostly grass and weeds up until end May 2013. I needed to put the wood chips somewhere, so decided this would be the storage area until used up, and then I’d see how well the underlying plant material had composted.

Above you see the storage area of mulch, under which is two layers of up-turned turf bricks (probably about 6-8″ deep) from dug-up pathways, sitting on top of a grassy/weedy area.

Through the rest of the spring I continued to use up the mulch on paths through the back and the front, as well as mulching the perennial and mixed  beds and borders.  The neighbours and their friends did  likewise–it was a lot of wood chips!

Now here it is Autumn, and this is what has happened to all that turf:

DSCN2107

A few dead roots is all the evidence left of layers and layers of turf.

DSCN2106

Lovely dark soil, lots of worms.

So I’m convinced: Skip the cardboard, skip the manure, skip the grass-clippings–leave them on the grass! Call up your nearest arborist and get them to drop off a truck-load of wood chips. If you can’t use that much, invite your neighbours to read this blog post and then you can all share the bounty!

Most importantly, though, the first line in this post: “Autumn is a great time to PLAN…”. don’t leave the garden bed development to chance, or what is most convenient. If you can’t quite figure out where  you want to develop new planting beds, ask a neighbour or friend whose garden you admire. They’ll be sure to want to help you! Gardeners love to share their hard-won wisdom!

Comments? Questions? Love to hear it all. Don’t forget to click the “follow” link and the “like” button.

A Few Fertilizing Factoids

“Feed the soil and the soil will feed the plants.”

Plants don’t eat like you and I, they don’t have big gobs that scarf down every fat and carb molecule in sight (oh, sorry, that’s just me).

There’s something called the soil food web–a symbiotic relationship among all the elements of the soil, including microorganisms, earthworms  and macro organisms, inorganic decomposed stone (and not so decomposed!), all manner of organic matter including dead things–all existing together and benefiting one another. Well, maybe not benefiting the dead things…

I want to grow beautiful things and have a beautiful garden not so much for the sake or the plants or garden but as part of the greater beauty of creation. I look at the sky and I’m amazed at the blueness of it.

IMG_4222 2

And when there’s a tornado in New Brunswick I’m astounded at the power of it.

Slurped from amateur video on CBC.

Slurped from amateur video on CBC.

God’s creation is beyond our understanding, and appreciation.

I’d like to do it as little harm as possible, and even maybe do it some good, as a “good steward”.

So here’s some “factoids”:

1. Adding inorganic  fertilizers (I won’t identify the brands, but they’re the ones that DON’T say “organic”) will give your plants some of the nutrients they need (N–Nitrogen, P–Phosphorus, K–Potassium). Maybe a lot more than they need. At the expense of some of the microorganisms, who may find the “salts” too strong and die off as a result.

2. Even organic fertilizers can be overused: they will be slower to break down and filter into the groundwater, but if applied more than the plants need, they WILL filter into the groundwater. Any fertilizers should only be used if needed.

3. Every living organism need more than just N-P-K, but typically the inorganic fertilizers don’t have the iron, manganese, boron etc that we all need in trace amounts. Many of the organic ones do. Read the label.

4. Using organic mulch in moderation is probably the safest way to benefit the whole soil food web: slow to break down so less leaching of nutrients into the groundwater, feeds many of the inhabitants of the ecosystem, which benefits the whole, amends the physical quality of the soil, making it lighter and allowing root penetration.

And now: a completely unrelated poll:

Challenge:

What are your thoughts about use of fertilizer? Yes or no, good or bad, relevant or irrelevant? Let’s get a discussion going. Comment, share, question, dispute (nicely).

5 Tips To Understanding Plant Labels

So here’s the 5 main things to understand when you buy plants:

1. Hardiness Zone

2. Average Mature Size

3. Sun Exposure

4. Watering Needs

5. Planting Instructions

Hardiness zone.

This can be unnecessarily complex: there are USDA Plant Hardiness Zones which includes Canada, and bases hardiness zones on average minimum winter temperatures; Plant Hardiness Zones of Canada, which also uses average minimum winter temperatures but is different from the USDA zones; and Sunset Zones, which are much more comprehensive, using average warm and cold temperatures, humidity, length of growing season, and other factors, but which unfortunately is seldom used on plant labels or any other resource.

Most plant labels, even plants that are sourced in Canada, will use the USDA zones, so let’s go with those. Here in coastal BC most of us are in Zones 7b (slightly less cold than 7) to 9a. So bottom line here is that plants that are “hardy to zone 10” will generally die in average Metro Vancouver winters, and therefore are what we generally call “annuals”. But “hardy to zone 8” means we’re fine. This is the label to Rhodo ‘Jingle Bells’, Zone 7.

DSCN1530 DSCN1531There are a few things you can do with zones, first of all knowing what your own zone is: Here’s a great little site that you can zoom in and find your own almost neighbourhood zone. For example, I live in south Burnaby, zone 8b. Parts of North Burnaby are zone 9a, because it is closer to the protected Indian Arm of Burrard Inlet. Another thing about zones, is that you can “bend the rules”, depending on your own gardens microclimates. If you have a sheltered spot from the wind, you might be able to grow things that are technically rated as needing more winter warmth. There are lots of ways you can push the boundaries; that’s what Google is for. OK, enough already about zones. Let’s move on to…

Average Mature Size.

The above label says the “average size” of R. ‘Jingle Bells’ (implying “mature size”) is 3′ tall and 4′ wide. When you’re planting say two of these, the distance between the trunks of the two should be at least 4′. If you plant it next to something that grows to 6′ wide, you’ll want to have 5′ (radius of one plus the radius of the other)  between the two trunks. Knowing its mature height allows you to determine if you can plant something nearby that will look good towering above it, or if it would comfortably shelter something growing underneath it.

Now here’s a classic example of unhelpful;

Nunccio's Pearl

Nuccio’s Pearl Camellia

Here’ s the unhelpful part:

DSCN1535

Note the “Average Landscape size”. CLICK on the picture if it’s too small.

“Slow growing to 6 to 8 ft. tall and wide, larger with age“. So if it doesn’t grow older, it won’t grow bigger. I’ve planted it in front of Rhododendron ‘Johnny Bender’, hoping that JB will grow bigger than the label says (5′ T and W) and that NP will NOT “grow larger with age”.

Sun Exposure.

A quick primer on Sun/Shade Exposure, starting with: spend a few days in various seasons watching where the sun hits the ground in your many garden areas.

Full sun: 6+ hours of direct sun

Part Sun or Part Shade or Dappled Sun or Light Shade: 4-6 hours of direct sun, maybe divided into early morning and later afternoon, or all early morning, or all later afternoon, or right across the hottest part of the day.

Full shade: At the most 1-2 hours of direct sun. But if your full shade has lots of full sun nearby, it’s still pretty light, and might support lots of “light shade” kinds of plants.

North-facing front yard. house casts full shade on the rhodos, but the rest of the yard is in full sun all day. The shade is bright shade even tho' it gets no direct sun.

North-facing front yard. House casts full shade on the rhodos, but the rest of the yard is in full sun all day. The shade is bright shade even tho’ it gets no direct sun. And even tho’ in this picture it looks like NIGHT.

Dense Shade: not only no or minimal direct sunlight, but lots of dense things hiding sun: like your own building and a highrise 20 feet away, and a 50′ cedar over to the right, and a maple to the left. That’s DENSE shade.

“South Facing” or “North facing” or whatever doesn’t always mean much. My “North facing” front yard is actually in full sun from 8 am until 8 pm. (in the summer), while my “South facing ” backyard has lots of areas that have no direct sun ever.

Water Needs and Planting Instructions

Almost every plant tag will recommend “fertile” soil. (There are a few plants that actually prefer poor soil, but that’s for another day…). So let’s assume you have decent topsoil and a little organic matter (compost, sesasoil, mushroom manure…) added. Once you have soil that will support decent plant growth, you should place together plants that have similar watering needs. For example, many sedges are the kind of plants that grow along river and lake edges, so should be in really moist soil. Don’t plant them in raised beds that will dry out quickly (unless everything in that bed needs to be in really moist soil). Lady’s mantle (Alchemilla)  and salvia are very happy in drought conditions (after giving them a few months to grow deep roots). So plant them together and don’t water them like the sedges.

plant labels d

Note the Care Instructions

Good plant tags will include watering instructions, but they don’t take into consideration what else might be going on in your garden–which of course the growers can’t do! Most plants need excellent watering their first year after transplantation (from the grower’s environment to your environment). After that they should only receive the amount of water they would need in their native climate. Many plants won’t need any extra watering above what we get in an average growing season. Best practice: grow plants together that have similar food and water needs.

There’s so much more to say on all these subjects, so if you have questions, do post them and I’ll either give you answers or direct you to answers. As always, look forward to your comments; click on the follow button to get regular posts fro RLGS.

Starting from Scratch? Tips for a Newbie Gardener

I just read this great beginners’ tutorial on starting a garden from Houzz. This isn’t for the person who is building a house and installing a garden completely from scratch, but rather for the person who looks at what they’ve got and has no idea where to start, or if they even want to garden at all.

So here’s the Reader’s Digest version: Clean up. Weed and Edge. Stepping Stones. Mulch.

1. Clean up.

I have three unsightly cedars on the edge of my front yard. They drop detritus like crazy in the winter, hiding everything that’s of any interest or beauty underneath it. By clearing that away, I see all kinds of things that I can’t see until I clean up. Even if there’s only lawn (even crappy lawn like above), or even only “dirt” (which gardeners call “soil”–dirt is a dirty word!), neatening it up will give all manner of gratification (as you can see above), and hope for what’s to come. Cleaning up may include pruning–I’ll get to that in a future post!

2. Weed and Edge.

To begin with, weeding may be quite intimidating, and not a little work. But once you’ve cleaned up the site (as above) so that you can see what’s there, and tackle small areas at a time, it’s not nearly as bad as anticipated. And definitely gets easier as you keep at it. Mulching (step 4) REALLY helps.

Then take an edger–or even an old long serrated knife will do nicely–and cut a sharp edge to the garden beds. You’ll be surprised what  an effect it creates. And in the same way, neaten the edges next to sidewalks, driveways and paths.DSCN1333

3. Stepping Stones.

Randomly positioned repurposed pavers

Randomly positioned broken, repurposed “grass pavers”.

One of the chief things about getting going in the garden is accessibility. The easier it is to get to all areas of the garden, the more you’ll wander in there, and the easier it is to do whatever needs doing, whether it’s weeding, planting, evaluating, watering…

So find something that will serve as stepping stones, and then find lots of places to put them. Your  goal is to make all the little nooks and crannies of the garden easily reachable. Bricks will do, flat stones, tiles, concrete rhubarb leaves (my favourite!).

Rhubarb leaf stepping stones in the veg garden.

Rhubarb leaf stepping stones in the veg garden.

4. Mulch.

Once you’ve dealt with the current generation of weeds, you’ll want to prevent more growth as much as possible. This is (one of the many areas) where mulch really shines. Put 2-4″ of some kind of (preferably organic) material that covers the soil. My choice is wood chips, that I got free from a local tree service. Compost or composted manure will also do, as will bark nuggets if you must. Pea gravel will work if that’s the look (modern, edgy or desert) you want. The further weeds have to travel to reach light, the weaker they become and the easier they are to pull. There will always be weeds, so let’s make them as little work as possible. And covering the ground, especially with organic matter, improves its quality, always a good thing. Better soil is a less desirable environment for weeds–they are generally opportunists that take advantage of empty or poor soil. Or not:-P

An area in permanent shade that has never been mulched or in any way improved. Weedy!

An area in permanent shade that has never been mulched or in any way improved. Weedy!

Does this help you get a sense of where to start in your new space? Let me know in the comments section, and as always, ask questions, make comments, share to FB or whatever.