Lawn Management 2017

A Better Lawn

There are a lot of issues involved in keeping a pretty lawn here in coastal BC.

First of all, the explosion of European Chafer Beetle in the last 8 years has seen many lawns decimated as tho’ someone had taken a rototiller to them.

My “lawn” Dec 31 2014. Lots and LOTS of racoon damage–they are searching for Chafer Beetle grubs, and clearly they’re finding them… Click on the picture for a good look at what they did!

Next there’s “summer dry” (can’t call it “drought” when we’ve seen what real drought is like!), and our expectation of watering restrictions. Even without “dry” we have the restrictions, but you (may) remember the summer of 2015 when we were perilously close to Level 4 restriction, which would have prohibited watering even vegetable gardens! I know–crazy!

Then there’s the increasing awareness of the environmental cost of fertilizers and pesticides. And I’m not even going to differentiate between “chemical” and “organic” because a. they’re all “chemical” (everything is chemical!), and b. so-called “organic” products can be as dangerous as the …other… products.

What else? Well I guess this year there’s “Snow mould”–a fungal disease that I’ve never seen before, and I understand is related to number of days of snow coverage. We’ve had more snow coverage in most parts of coastal BC than I’ve seen in my 35 years here. Will it happen again? Probably, so we should know something about its management.

So the following management protocol is going to address all the above concerns. I’ll try to explain as I go along, so this may be a pretty word-intensive post.

Management principles (not in any particular order):

  1. Feed the soil not the lawn
  2. Tolerate a few weeds.
  3. Encourage deep roots.
  4. Remember the lawn is part of your garden

Some Kind of Protocol

It’s Spring, so I’ll start off with Spring tasks. Your lawn is flattened (especially this year), has a lot of brown grass blades, possibly some bare patches, possibly snow mould, and very possibly the critter-damage as seen above. Or maybe more like this:

Crow damage due to Chafer Beetle infestation.

Maybe moss, like above, if your lawn is shaded by a tree canopy or your house, or your neighbour’s house.

Lawn turf consists of lots of individual grass plants, most of which multiply vigorously  by means of running “rhizomes”. If you’ve had to remove grass from your garden beds, you’ll find strings of roots, with little grass plants sprouting up intermittently. That’s what they’re supposed to do in the lawn. Which incidentally is what they will do at the edge of the lawn as it interfaces with your perennial border. I edged my own garden beds with bricks, but those determined grass rhizomes creep along the brick until they find the gap between two, and scoot in between to find really great growing medium. Now I always edge client’s lawns with some kind of either decorative or invisible border (not horrible black plastic!) and then often a soldier course of stone.

If your turf looks like either of the above pictures, it’s not recoverable. Yes, you could remove all the debris, fill up the holes with turf-blend soil, and over seed. But getting it even, level, and somewhat matching will be a challenge. Both lawns were removed completely and replaced with “something completely different”.

Pond July 27 2016

Almost done

But assuming your lawn isn’t that bad, Spring calls for clean-up, soil-feeding, and grass boosting.

Clean-Up

There seems to be a lot of Snow Mould out there. It looks like a layer of matted dead grass. Since I was completely unfamiliar with it–it’s uncommon here in coastal BC, but with the prolonged snow cover, the fungus had a field day taking hold–I had to do a fair amount of research to understand it and learn how to manage it. Gently rake over the lawn to remove as much debris as possible without ripping up the roots. For the homeowner it’s unlikely the snow mould has killed the grass, but as long as the ground is cold and wet, the fungus is probably still proliferating. Raking up as much as possible will decrease the “disease load”.

Snow Mould

This looks like surface water, but it’s a film of fungal growth sitting on top of matted grass.

Moss

If you’ve got a lot of moss in your lawn, you’re going to be tempted to try to rake that out as well. I recommend against trying! Moss growth is a function of moisture, shade, and to a lesser extant, low pH. Because of our constant rain, our native soil here is acidic. Not severely acidic, but enough to encourage moss growth and discourage turf grass growth. The same rain also keeps the ground wet for long periods of time–like 10 months of the year! And the same rain makes trees grow big, providing lots of shade. W can’t do much about the rain, but we can improve drainage, light, and pH.

Soil Feeding

Which brings us to soil feeding. Contented soil–that is, the soil that will support great turf grass–is almost neutral pH–around 6-6.5, well-drained, with organic matter comprising 5-10% (less than many people think is optimum), having been exposed to little if any fast-acting/water-soluble fertilizer and little to no pesticides/herbicides.

When I first moved into my current home, I found NO earthworms in the ground when I dug into it. The lawn had probably only ever been treated with fast-acting “weed-and-feed” products which would have killed many of the organisms in the soil and promoted green top-growth of grass at the expense of deep roots. Fast-acting and water-soluble fertilizers are also main culprits in the algae bloom problems of local waterways because the turf will never use up the products as fast as they are being washed into the groundwater or storm drains. The soil was also pretty sandy, so for sure the lawn was never top-dressed with compost.

Aerating is something that will benefit most lawns. If you have relatively heavy soil, or the lawn experiences a lot of foot traffic, or it’s a new construction, or for any number of reasons, your soil may be compacted. This decreases the actual air pockets and therefore the available oxygen in the soil, so there’s less life down there! And life is what you want. Core aerating is when you go all over the lawn with a tool or machine that takes goose-poo sized “cores” out of the ground, usually around 10-20 per square foot. You can do it with a funny tool that you step on Like this Hound Dog, which I’ll readily warn you is a lot of work, especially if, like me, you have a lot of stones in your ground. But if it’s a smallish space, and since you’re only doing it once every year or two, it’s the simplest. Alternatively you can rent a power core aerator. What you don’t want to do is just “spike” the lawn without actually removing cores; in that case you’re making spaces, but increasing the compaction all around the spaces.

Related to core-aerating the lawn, is making sure there’s no standing water. Unless you’re growing Bald Cypress or Mangroves, you want to be able to walk across the lawn and not leave a depression, or experience that squishy feeling. If your ground is that wet, you’ll have to do something a bit more structural to fix the problem–swales, French drain, gravel pit. There are a number of options, all quite a lot of work but necessary if you want lawn.

Top-dressing

At least once, and even twice a year, your lawn should be “top-dressed” with ¼”-½” of some kind of well-composted matter. It may be your own compost, it may be municipal compost (this isn’t your food garden, so the “non-organic” nature of municipal compost is not an issue here), or it may be bagged compost like Sea Soil. If you’ve got a large expanse of lawn to treat, you could get in a few yards of a “turf blend” soil, which will be something like half composted yard trimmings and half sand. Rake it over the lawn so you can see all the grass blades coming through it. This will feed your soil, and the sand in it will contribute to good drainage. Adding a modest amount of organic matter to the ground every year will improve every kind of soil, from the sandiest to the clay-iest.

So you’ve just given the organisms in your soil a breath of fresh air, and breakfast lunch and dinner. You’ve got contented soil. Or at least you will have contented soil if you do this every year. For now you’re on the right road at least.

Over-Seed

And once you’ve got a nice little layer of compost down, over-seed with lots of appropriate grass blend. You know that the  birds are going to take their share, and there’s little you can do to prevent that. So just make sure you’ve got enough grass seed down to feed them and the lawn. I heard someone say every seed should be touching another–which means you’ll barely see the compost through the seeds!

There’s been a lot of talk locally about the newest development on the block–use of tall fescue (which isn’t actually tall) grass seed. It’s pretty resistant to the chafer beetle damage (apparently they don’t find the roots as palatable as other turf grasses), and puts down deeper roots to take advantage of moisture at deeper levels.

Adding a small percent of micro-clover (probably 5-10% by weight) will improve colour, summer drought tolerance,and being a legume, will convert atmospheric nitrogen into soil-bound N. 

Grass boosting.

Grass plants have simple needs–like most of us; we don’t need the toys of modern life and are often better off without them. Grass needs air–we’ve dealt with that by aerating. It needs food–the organisms feed the plants, and we’re feeding the organisms with our compost, and by not killing them with herbicides and pesticides. Two more things grass needs is a neutral pH, and light!

Without providing your grass plants (remember, each blade or couple is a separate grass plant, so think of it as an extension of your “garden”), optimum or at least adequate light, your lawn will never do well. Under ever-growing trees, in the north side shade of the house, these are areas that turf grass will always struggle. You can amend shady areas by thinning deciduous trees, or limbing up evergreens, and thereby allowing more light escaping to ground level. And if at the same time you sow a shade tolerant grass blend, you may get the lawn you’re after. (Microclover incidentally likes full sun!)

The pH is increased very gradually by “liming” the lawn. Now professionals always tell us to get a soil test to find out what is deficient before we try to correct it. And in principle of course I agree. But back to our high rainfall, calcium and possibly to a lesser extent, magnesium, are “leached” from the soil by constant rain. Now I’ve read that many times, and still don’t completely understand it, so if anyone can explain it to me I’d be grateful! Whether I understand it or not, tho’, our native soil is acidic. Compost breaks down to neutral pH, so adding that will aid in neutralizing your soil. As does judicious application of lime–either Calcium Carbonate agricultural lime, or dolomitic lime, which has Magnesium carbonate as well. Every resource I read suggested only liming every 2-4 years, since it is so slow to change the pH of the soil. But I remember Brian Minter saying twice a year wasn’t too much in our climate! Quite a difference. But if you stick to a maximum of 35 lbs/1000s.f., seemingly you can’t over-lime.

Now I haven’t mentioned this, since after all it is a blog post on lawn management, but if you have shadey, chronically dry, chronically soggy,  highly acidic, or heavily trafficked areas, you might consider not  trying to grow turf grass. Just sayin’…

So…How?

  1. Deal with drainage. The sine qua non of lawn care.
  2. Lime.
  3. Core aerate.
  4. Top-dress with compost
  5. Over-seed

Using tall fescue as one of the grass species in your blend will help deter chafer beetles. It will also do better in summer dry. Using a little microclover will naturally add nitrogen to your soil, and also give it more drought tolerance. Not using man-made fertilizers and pesticides–in fact natural pesticides as well–will allow the beneficial microorganisms in the soil to do their beneficial thing, and limit the negative environmental impact of your lawn–maybe even give it a postive environmental impact. Your microclover and compost will add N and other necessary elements. And all the above will help prevent snow mould should we have another winter like this one.

Sounds pretty simple, eh?

How to Prune Ornamental Grasses

How To–Ornamental Grasses

I wanted to post this several weeks ago, but then we had another dump of snow (haven’t heard the stats, but more snow this winter than I’ve experienced in my many years here on the Wet Coast!)

But it’s now seasonably warm, the ice all gone and most of the snow, so I got out yesterday and trimmed my ornamental grasses.

Carex comans 'Frosted Curls' Sedge

Carex comans ‘Frosted Curls’ Sedge

Northcoast Gardening has a great series on pruning ornamental grasses, and I checked it out before starting my own.

The other thing I checked before starting was whether I wanted to start at all yet. There are still seed heads on some of the grasses (admittedly not that many) and I love to leave them for the birds. And of course, one of the main reasons for not trimming down your grasses in the fall is the winter interest they provide while all your herbaceous plants (think Hostas and Daylilies) are completely dormant and underground. Not a problem when the ground is covered with snow, but we seldom have snow, so the alternative is an expanse of soil or (preferably) mulch.

Two observations made my decision: it’s warming up and things are starting to “bloom and grow”, and I don’t want to find myself cutting off bits of new growth while eliminating old growth. And the unusual volume of heavy wet snow over the past two months has done to my plants what the rest of the country experiences every year–made a mess. It’s making me re-think my “no Fall clean-up” philosophy…

Thus

I started with the Mexican Feather Grass (Stipa tenuissima, recently renamed by the botanists as Nasella tenuissima for who-knows-what-reason).

Mexican Feather Grass, Stipa tenuissima.

Mexican Feather Grass, Stipa tenuissima.

This jumble of grass is three MFGs on the right, a Frosted Curls centre and another to the left of the pic, all helping to hide the waterfall reservoir, which unfortunately you’ll see later on…

Stipa tenuissima

Stipa tenuissima

With a lot of grasses you can use a method of pruning not unlike combing hair. Using rough gloves–rubbery or leathery–just reach down to the base of the grass blades and comb. Most times you’d use this method if there’s still a lot of green present in the clump.

Combing though grass

Combing though grass

This system has worked best for me when I’m tidying up at other times in the year, especially getting rid of particularly messy seed heads (notwithstanding what I said before about leaving them for the birds. Sometimes they’re just too messy!) It didn’t work at all yesterday for the MFG. So instead I did the ponytail thing:

Mexican Feather Grass, aka "Ponytail Grass"!

Mexican Feather Grass, aka “Ponytail Grass”!

Just grab and cut

Just grab and cut.

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Not putting this in the compost since it’s full of seeds, and my compost isn’t hot enough to kill the seeds. As it is, the seeds that have dropped in the garden last summer/fall will germinate and I’ll have dozens of babies all over the place.

 

Dead bits in the centre

Dead bits in the centre–you can see the bits I pulled out up at the tip of the pic.

This particular plant has been in this spot for about three seasons, and clearly it’s time to lift and divide. Many plants really need  to be divided every few years because the centre rots or otherwise dies out, and the rot/death can spread to the rest of the plant killing the whole thing. But when you see this happening, or if one year your grass just doesn’t grow very well, it’s the signal to lift and divide. When I do it in a few weeks time (could have done it yesterday but…didn’t) I’ll show you how.

Carex

On to the Carex:

Carex 'Frosted Curls'

Carex ‘Frosted Curls’

Carex 'Frosted Curls'

Carex ‘Frosted Curls’

This still has lots of green visible, so I’m not going to chop it down like the MFG, just comb it. The one at the top of this page is even greener, so I didn’t do anything with it.  The others however are totally straw-y, so cut them right back into little porcupines. You can see that I left a little height on the “straw”, as much for convenience of cutting as anything else. It’ll be hidden by new growth.

Carex after a haircut.

Carex after a haircut. Make it a really short haircut so the old growth is completely hidden by new growth.

Other grasses

This Japanese Forest Grass is really offering no particular beauty to the garden but I still decided to leave it as is:

Japanese Forest Grass--Imperata cylindrica

Japanese Forest Grass–Imperata cylindrica

Imperata cylindrica 'Red Baron'

Imperata cylindrica ‘Red Baron’

The JFG is really slow to sprout, so rather than forgetting where it is and digging through it by accident, I decided to leave the detritus for now. I’ll check regularly for new growth and cut this right down to the ground as soon as there’s anything to see–which won’t be until well into Spring. Japanese Forest Grass (or Hakone Grass–Hakonechloa macra) behaves much the same.

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Miscanthus sinensis ‘Dixieland’

Miscanthus sinensis 'Adagio'--or is it 'Yaku Jima'?

Miscanthus sinensis ‘Adagio’–or is it ‘Yaku Jima’?

The Miscanthus(es) above can be treated the same as the MFG. Note that these two varieties are dwarf and therefore pretty easily managed. Larger Miscanthus (aka Maiden Grass) require a slightly different method which you can read about in Northcoast Gardening.

Pennisetum alopecuroides 'Red Head'

Pennisetum alopecuroides ‘Red Head’

Panicum virgatum 'Prairie Flame'

Panicum virgatum ‘Prairie Flame’

The Panicums (Switchgrass) and Pennisetums (Fountain Grass) are also treated the same.

So what isn’t treated the same?

Phormium tenax --New Zealand Flax-- and Festuca glauca--Blue Fescue

Phormium tenax –New Zealand Flax– and Festuca glauca–Blue Fescue

These two.

The Blue Fescue will probably only need a light “combing” to get rid of dead leaves, but every 2-4 years will want to be divided to maintain the shape we all know and love. And the Phormium should only have the tatty-looking blades removed right down to ground level. If they get to the point where most of the blades are in rough shape (what are they like now after all our heavy snow?), the whole plant can be cut back to ground level. Unfortunately, they’ll be slow to return to they’re former beauty…

Questions

If you have questions about your own grasses, feel free to post them here and I’ll get back you with either an answer or more questions.

Designing on Computer

I’m re-learning a landscape-based CAD program–Dynascape. I haven’t decided what to do about colour–whether to hand colour or invest in the colour plug-in. In the meantime, I’m enjoying learning…

Planting Plan--includes all the plant labels.

Planting Plan–includes all the plant labels.

Presentation Plan--this would be the simplified version for the clients so they're not overwhelmed with detail.

Presentation Plan–this would be the simplified version for the clients so they’re not overwhelmed with detail.

Wisteria

Wisteria

This article about Wisteria in Gardenista reminded me of an assignment I did in Landscape Design. I can’t remember any details of the assignment except that the “client” wanted Wisteria growing up and over an arbour. One of the other students felt it was wrong plant wrong place and asked to just omit it, but the instructor insisted it was non-negotiable. I omitted it. (It’s just now occurred to me that maybe it was meant to be a trick question–as in, what would we have to do to the arbour in order to make it compatible with Wisteria…?)

I’m sure you’ve read the article (it’s short and pretty), so I’ll just quote its main point:

You invited them to stay for a few days, and now it has been weeks. Although you asked them to stow their bags on the luggage rack and place their coats and boots in the mudroom, their belongings are strewn helter-skelter all over the place. You check the fridge and notice the groceries you stocked this morning are almost gone. At your wits’ end, you wonder, what do I say to these inconsiderate guests?

That’s how Wisteria sinensis behaves, (described in Wikipedia as “beautiful but ruthless Chinese wisteria”) but because it’s a plant and not family, you can be a strict disciplinarian with it. (FYI, “American Wisteria” or Wisteria frutescens is a bit smaller, a bit less aggressive, with smaller and therefore less messy flowers. But it’s still Wisteria!)

  1. It grows quickly, so even if you’re really good at pruning two or three times a year, it’s still growing bigger underground, and its “stem”, aka “trunk”, is also growing. So it’s getting really heavy. Unlike my fictional client in the assignment, you can choose where to plant it, and if the best spot is over an arbour, strengthen that arbour, or replace it with something that’s really sturdy!
    This is NOT a suitable arbour for Wisteria!

    This is NOT a suitable arbour for Wisteria!

     

  2.  Even better, IMHO, is to train it to a tree form. (Check out that Youtube video–the tree in bloom at the end of the 3 minutes is amazing!)
    Tree form wisteria

    Tree form wisteria

    This above wouldn’t be my preferred wisteria tree, (I prefer the one in the Youtube video), but kudos to these homeowners for trying. Or the landscape designer for choosing it.

  3. I’m pretty sure I had a picture of wisteria trained along a chain link fence, but can’t find the pic. It was severely curtailed, but successfully covered the fence (only 40” high as is allowable for a front yard fence) without looking out-of-control.
  4. Bottom line is: prune, prune, prune!

The Goodness Ratio

I’ve stolen that expression from Darcy at egardengo and I hope he won’t sue me for copyright infringement. The principle goes like this: the more valuable space a plant occupies in your garden, the more it has to perform for you and the less you should tolerate its shortcomings.

For example: Here is the exquisite Rosemary Harkness rose:

Rosemary Harkness

Rosemary Harkness Rose

I’ve enjoyed her blooms for over 10 years. But at her very best she bloomed little, and at her worst she had gangly canes and was covered with black spot. Never an attractive shrub. And while I didn’t need the space she occupied, I put up with her deficiencies for the sake of the few but beautiful blooms.dscn2853

No more. I wanted to plant a ‘Bluebird’ Hibiscus syriacus (Hardy Hibiscus) that my neighbour was discarding, and the best place for it was right about where Rosemary was. So Rosemary is no more. Shovel pruned, as they say. There are lots of other, better performing apricot-shaded roses, so why have one that has never earned her keep.

So look around at your garden objectively to see if the plants are fulfilling their designated function. If not, and they don’t “put a smile on your face”, consider replacing them with better choices.

Hibiscus syriacus 'Blue Bird'

Hibiscus syriacus ‘Blue Bird’ –too low a “Goodness Ratio” for my neighbour, who wants the space for apple trees. 

Blue Bird

Blue Bird–Her loss is my gain!