Tag Archives: killing moss

Of magnolias, mood lighting and more on Cold Water Surf

Just another unnamed seedling

I feel that we are becoming increasingly reclusive in this new world we are facing in 2020 but there are many worse places to become reclusive than here. It is magnolia season.

Magnolia × soulangeana ‘Alexandrina’

It is time for my annual reminders on magnolias.

  • If your magnolia opens with two separate coloured blooms (white first and with deep red just opening in the email enquiring about this phenomenon this morning), you have a case of escaped root stock. The root stock is generally stronger growing and will overwhelm the grafted variety over time, if you don’t remove it. This is not a case where you can have two for the price for one.
  • Ripped petals are usually being eaten by kereru, sometimes rosellas in northern parts of the country. Kereru are a protected species, rosellas are a gaudy Australia export so not.
  • Buds which fail to open or only produce distorted, misshapen blooms have almost certainly been eaten out in the bud stage by possums or rats who like to nip out the centre. Mark carries out extensive trapping and shooting to keep these pest numbers low here.
  • If you are into spraying your lawn in spring, do it now. If you delay, the faintest whiff of spray drift as magnolias start to open their leaf buds can cause significant damage to the new foliage which will be unsightly until the leaves drop next autumn and, over time, can weaken the tree.
  • It might be true in the UK that you can’t move magnolias – or it may be a factoid – but here in NZ we can move magnolias and we have done it many times. Just make sure you get as big a root system as you can manage and if the root system is small, prune the tree hard.

Lanarth at the top, Mark’s purple below

We have been hesitating about whether we can fairly describe Mark’s selection (as yet unnamed) as purple. Magnolia campbelli var. mollicomata ‘Lanarth’ is widely seen as setting the standard for purple magnolias. I finally got around to lining up petals of Mark’s purple and Lanarth petals to compare. Magnolias are variable so I picked up the darkest petals of Lanarth I could find and it seems that the colour of Mark’s measures up.

Top to bottom: Lanarth, Mark’s purple, Vulcan and Burgundy Star

Just out of interest, I added in Vulcan petals. Vulcan was the first of the new generation magnolias 30 years ago that moved into red tones, rather than purple. The few at the bottom are of Burgundy Star, the next generation of reds bred from Vulcan. Mark is getting to cleaner reds.

More on Cold Water Surf (or any other washing powder) and moss. You can, and I have, use it on moss in the lawn. We accept moss but preferably the fine forms. I am not a fan of liverwort and some of the coarse mosses and Surf works on them.

Hard surfaces? Hmmm. It works. It kills the moss. If all you want to do is to get rid of slippery growth, it may be fine to sprinkle it generously, wait for rain and then use a stiff brush a few days later. I want these pavers back to their soft gold so I tackled these with a wire brush but it is going to be a lot of hard work to restore the whole area. I think I will resort to the water blaster (jet washer).

Finally, a few mood shots from this week. We do not generally get mist or fog so this morning mist gathering in a lower area seemed appropriately mystical to me.

On a grey morning, a few shafts of rising sun broke through to illuminate the magnolia in the distance. It was a somewhat startling sight.

Fairy Magnolia White

More often, this clarity of light is the norm for us, even in winter. That is Mark’s Fairy Magnolia White which really does have an exceptionally long flowering season.

It is August – time for magnolias, laying paths and killing moss

Magnolia campbellii ssp mollicomata ‘Lanarth’

Lanarth down by the water in our park

As August arrives, there is so much happening in the garden. Every day sees something else in bloom and now I get anxious that if I forget to look for a few days, I might miss something. I tell you, spring can be stressful.

Mark’s yellow Lachenalia reflexa hybrid

But our thoughts go out to overseas readers whose lives continue to be disrupted, discombobulated and sometimes turned upside down by Covid-19. Never has New Zealand felt so comfortably remote and self-contained, a small cluster of islands holding the unpredictable forces of chaos at bay, so far. May you stay safe and well, wherever in the world you are.

We are inching ever closer to finishing the new summer gardens, or at least to completing this stage of development. There are just the path surfaces to be laid and that has to wait until the man I hope can deliver the materials and arrange a bob-cat returns from holiday next week. We solved the problem at one end where the steps down to the garden were at a lower level than the camellia and michelia hedge that forms the backdrop. It was always going to involve some means of separating the levels. We priced steel edging because I really like that au naturelle, unobtrusive, thin look of gently rusted steel. Buying the branded product specifically designed for garden edging was very expensive indeed and that was without factoring in freight. Ever-handy Lloyd priced buying the steel locally, cut to suitable size, and it came in at about a third of the price but still somewhere over $1000. It was not going to bring me enough pleasure to warrant spending that amount of money.

Compromising with a stained timber edging

Much and all as I dislike tanalised timber in the garden, I compromised and said that would be okay as long as we stained all bits that will be visible to charcoal black. It was a solution that cost $103 (to buy six metre lengths of timber) and once the paths are laid, I do not think it will be obvious at all. The paths will be built up by about eight centimetres so there will not be a whole lot left visible.

A handy bobcat back when we started work on these gardens

Because it is going to take up to 30 cubic metres to lay all the paths, our plan – subject to the advice from the man currently on holiday – is to lay a base core of pit metal compacted to about 3 or 4cm deep and then lay the crushed, creamy yellow limestone on top of that to another 4cm. We think the pit metal will be much cheaper than limestone. We need to hire a bobcat and operator because none of us want to be carting 30 cubic metres of anything and the bobcat will be able to do a lot of the compacting that is necessary. If you have never seen a bobcat operating, believe me they are fast, manoeuvrable and quite mesmerising to watch.

On another practical level, a packet of Cold Water Surf washing powder entered my life. I had forgotten about its existence. It is vile, over-scented stuff that I would never use in the laundry but others may not mind that overpowering scent of chemical fragrance. We use unscented washing powder in this household of sensitive skins. But damn, that Cold Water Surf is a whizz on killing moss.

People in drier climates will not relate to the issues of excessive moss and lichen growth that we get here. There is nothing wrong with some, but we can get way too much. Sometimes we water blast (jet wash) the paths but that also takes off the surface of the concrete and flushes out any filling between pavers. It is just as fast for me to scrape off the top layer of moss, sprinkle Cold Water Surf to kill what remains and then use a stiff broom to sweep the residue off.

And it can kill very fast. This rather deep-rooted moss browned off within hours and died soon after.

I am no chemist so I struggle to get a grip on the difference between carbonate, bicarbonate and percarbonate. But as far as I can see, the active ingredients in many of the expensive, branded moss killers are often sodium carbonate (washing soda or soda ash), or sometimes sodium percarbonate (which is washing soda and hydrogen peroxide – a common ingredient in eco-friendly bleaches and other cleaning products).

You can buy both sodium carbonate and sodium percarbonate in powder form and I have done so but it worked out relatively expensive to use in the garden when cheap Cold Water Surf works just as well. Logically, this must mean that I was spreading the pure product too thickly when it can be extended by adding some sort of neutral carrier (Mark suggested sand). At a practical level, the products were fine powder and the coarser texture of the laundry powder makes it easier to spread evenly. Also, logically, any proprietary laundry powder should work unless some have a higher percentage of washing soda than others and that I do not know.

I am wondering whether it will work on our sandy coloured pavers in our front entrance courtyard. I water blasted these a few years ago. It was my first ever go on the water blaster and it took a lot longer than I thought it would. It was also wet and messy and blew out the sand between the pavers which Lloyd than had to refill. But they looked like new when done. Now they are blackened and discoloured again. I know there are branded products that attach to the hose that will also work and are quicker to use, albeit expensive. If laundry powder will do it, that appeals to my economical nature and avoids buying another product sold in a hard plastic container. I shall experiment and report further.

Narcissus Peeping Tom

Garden lore

It is a curious thing that people will sometimes spoil some garden project for the sake of a word. For instance, a blue garden, for beauty’s sake, may be hungering for a group of white lilies, or for something of palest yellow, but it is not allowed to have it because it is called the blue garden and there must be no flowers in it but blue flowers…. My own idea is that it should be beautiful first, and then just be as blue as may be consistent with its best possible beauty.

Gertrude Jekyll Colour in the Flower Garden (1908)

Dealing to moss

The easiest way I know to kill moss growing in the wrong places is to lightly sprinkle soda ash. This is in fact powdered washing soda (sodium carbonate or Na2CO3 for the scientifically inclined) and you can buy it from bulk bins. Cold Water Surf is often recommended and does work. I am guessing Cold Water Surf contains a relatively high proportion of soda ash as a water softener because it works much better than the budget washing powder I tried. Having found what the active ingredient is, I now prefer to use straight soda ash without the unnecessary extras. It is non toxic and occurs naturally so, as far as I know, is not going to harm the environment. It kills moss overnight though you then have to wire brush the dead moss off hard surfaces or rake it out of lawns. Experiment lightly – it doesn’t take a lot to be effective.

Published in the Waikato Times and reprinted here with their permission.

In the Garden: November 4, 2011

The start of a new fortnightly series first published in the Weekend Gardener and reproduced here with their permission.

An easy method of killing unwanted moss

An easy method of killing unwanted moss

With our garden festival currently in full swing (now styled the Powerco Taranaki Garden Spectacular), all our efforts in the garden have been on presentation for the most important days of our garden visitor year. We call this garden grooming – a bit like giving your car a valet treatment. It doesn’t last long but it looks great in the meantime. When it comes to the lawns, we have made a deliberate decision to avoid chemical use where possible, both for weed control and fertilising. We use a mulcher mower, an edger and we hand dig flat weeds. As long as the rest is comprised of small, fine leafed green plants which mow well, we are willing to live with a mixed colony rather than just rye grass and fescue. At least our lawns are not toxic.

We don’t worry too much about moss in the lawns – it occurs most in shade where the grasses struggle. And if we were Japanese, we would revere the moss. But with our high rainfalls and humid conditions, we get a lot of moss growth on paths, brickwork and stonework. Often I will sprinkle soda ash (which is simply powdered washing soda crystals available from bulk bins) which kills the moss overnight. Indeed, cold water washing powders work equally well though I have found the leading brands are better than the budget brands – perhaps they have more water softener in them. Our chemist daughter reassures me that there should not be any problems of toxicity in using soda ash or washing powder to kill moss though if you get too carried away over time, you will be altering the pH of your soils because they are alkaline. I have experimented on grass and it kills moss without harming the grass. Do not do as someone I know – use so much that when it rained, his entire lawn foamed. The moss dies but does not disappear so you have to rake it out of lawns and brush it off hard surfaces.

Rhododendron seed head, missed from last year

Rhododendron seed head, missed from last year

Top tasks:
1) Deadheading rhododendrons. While conventional wisdom is that all rhododendrons including vireyas need deadheading, in fact only those that set seed need it. Setting too much seed can weaken a plant and even cause it to die over time. The others just look better for having it done.
2) Mulching garden beds. There is no point in mulching dry soils so we like to get it on before summer. We mulch frequently with homemade hot compost mix which means we rarely need to fertilise garden borders.
3) Getting the planting out of this season’s trees and shrubs completed. November is getting late for this but we soak all root balls thoroughly and can generally rely on regular rainfall here in North Taranaki.

In the Garden: August 20, 2010

  • The season of panic for gardeners is nigh. The slow moving cold days of winter are over and the rush of spring means the pressure is on to get everything done. Priority number one has to be pruning grapevines if you have them – their sap is on the move already. If you are not sure what you are doing, our Outdoor Classrooms on the topic (both winter and summer pruning) show how – click on the Outdoor Classroom topic to the right or type into the search box immediately below the photo of yours truly on the top right.
  • Kiwifruit are pruned in a similar manner to raspberries – take out old fruiting canes and weak growths, leaving the best of last season’s new growth to set fruit for next season. It is usual to tie kiwifruit along horizontal supports to increase crop yield and to keep them under control.. We saw them trained to cover pergolas in northern Italy where they were regarded as rather more exotic than here. They were very effective and we are thinking of trying it.
  • Keep sowing peas fortnightly and sow onions from seed.
  • Get a mulch onto the asparagus patch if you are lucky enough to have one. It is the optimum time for feeding this crop as it breaks dormancy and comes into growth.
  • It is the last call for using hormone sprays on the lawn, if you feel you must. After this next week or so, put the spray right away to back of the cupboard until all deciduous plants in your own and your neighbours’ gardens have put on their fresh foliage later in spring. You can cause terrible leaf damage which can last until leaf drop next winter, or even kill the plant in bad cases, with even the slightest whiff of spray drift at the wrong time.
  • It is the time for digging and dividing spring and summer perennials which will be coming into growth.
  • Do not delay on sowing new lawns or patching balding old ones. The lawn we showed in the last Outdoor Classroom is now a pleasing swathe of green though still very fresh.
  • Apparently the use of Cold Water Surf as a moss killer is widely known, judging by the calls I received after last week’s Countdown to Festival. And it is quick – I tried it on a mossy path and within three days it had turned brown. Don’t be too generous lest you be like the person who told me she laid it on so thick that her lawn foamed when it rained. Another caller told me it does not have to be CWS – any washing powder will do so I have bought the cheapest I can find to experiment. Be a little cautious though – it will either be the alkaloids or the phosphates or something caustic that causes the moss to die. In moderation, septic tanks show these are not a problem but you probably don’t want to carpet your environment in them. Vinegar also works.