Dealing with knapweed

Knapweed in moderation is quite an attractive wild flower, thistle like without the prickles. But too much is pernicious.

For most of the time we’ve been here we’ve been trying half heartedly to control it, mainly by snipping the flowers off before they seed. But lately it has got out of control in the meadow and blanketed large areas, inhibiting the fritillaries and orchids for which the plot is so valuable.

Knapweed two months after the summer mow of the meadow – growing back fast ready for next year’s assault.

So decision time: chopping it down does not make much difference because there’s a big root system and it regrows fast. The only serious way to deal with it is to dig it out clump by clump – so we did, using a deep and narrow trenching spade with a steel handle that allows a lot of leverage to be put on the blade.

The roots are tough so the soil can be shaken off easily enough by banging a clump against the spade.

The job takes a long time, and there’s at least 100 square metres of weed. But there doesn’t seem to be any really effective alternative as we cannot possibly use chemicals and mowing only persuades it to spread sideways and flat along the ground instead of up, rather like plantain in a lawn.

The aim is to do a couple of hours every now and then so that the whole lot will be out by the time the heavy frosts come.

The start of the job, with the first area cleared of knapweed.

The earth looks bare but it is bound to be full of grass and other seeds and will rejuvenate very quickly. Any knapweed seedlings with be searched out and destroyed as they sprout.

Care was taken to avoid too much damage to the remaining plants – though apart from cowslips and grass most had been blanketed out by knapweed, whose leaves are easy to distinguish from the cowslips scattered between the clumps.

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Water lilies

Water lilies are thought to be the most primitive proper flowers, but that’s not why we are increasingly keen on them. They’re just very beautiful.

It started with a gift of two plants from a neighbour a few years ago, but one died and one seemed to keep disintegrating. The culprits were ducks and moorhens, either picking them for nestbuilding or just plain carelessness as they swam through them.

One of two cages we made

So we built a net cage round our single plant and it began to thrive. It was made from fruit netting tied to round posts hammered into the bottom – it’s a natural not a lined pond.

Last year we picked up five more plants from the village flower festival, and netted them too.

They grew well at first, but ducks and moorhens were using the nets so much for perching that they tore them and broke them down and so they had to be regularly mended. As the netting came down it did quite a lot of damage to the plants.

Just after the cages were removed

We have now removed the cages in the hope that the plants are thriving well enough to grow faster than the water fowl damage them. As you can see from the photo, there’s a lot of duckweed at the moment, but the water lilies are producing flowers every day.

The drawback of the way we obtained the plants is that we have no idea yet what varieties they are.

We have one with large pink flowers, one with yellow flowers and four with white flowers of which one has a spectacular yellow yolk. There are three distinctly different leaf sizes. Some research is required.

There is one observation from this year that is very useful. Five of the plants are in plastic tubs (in which building clay for wattle and daub came). We drilled all over with one inch holes and filled with soil. After planting, an inch of gravel was put on top to keep the soil in.

One plant from the village flower show was in a proper water lily basket. It has grown far more strongly than the others, and rooted through the container into the pond mud. So much for our cut-price solution of using old tubs. Next year we will replant them all in purpose made baskets. We don’t mind if they do root into the pond mud as long as it produces vigorous growth that beats the predation of the ducks and moorhen.

This single plant bursts with growth even though it has the smallest leaves.

A new pondweed

After 5 years of dealing successfully with blanket and duck weed, a new challenge, potamogeton crispus, otherwise known as curly pondweed has appeared in the pond. A few plants appeared last year and the year before. This spring there are very large growths.

It is listed by the Royal Horticultural Society as troublesome and the advice us simply to pull it out to reduce the growth, though once in a pond it won’t disappear altogether. So when the water is a bit warmer, it will be waders on and into the pond to do some weeding. It is noticeable that the areas where I raked the bottom last November to clear debris there is almost none of the new weed, so that is another longer-term option.

The good news is that it’s quite easy to pull up and it also seems to blanket out blanket weed. Curly pondweed is sold as an oxygenator for small ponds and aquariums and only becomes a real nuisance in large ponds and lakes. Oxygenation is a plus, too.

How it got into the pond is unknown.  Our neighbours did have carp in a tank which they transferred to their pond, which connects with ours, so that is a possibility.

Scything the meadow

It was time to take on the tall grass of the meadow. The primrose, cowslips, fritillaries and pyramid orchids were all gone – the cow parsley and other umbellifers were setting seed. So out came the scythe and the whet-stone and back came the memory of the steady stance, the slow swing and the regular sharpening routine I learned some years ago at one of Simon Fairley’s  classes.Scything Aug 2016

The iris bed

Inspired by Painting the Modern Garden, the exhibition at the Royal Academy earlier this year, the gift of a book on iris from a friend on my birthday, and some wonderful flowers in Tuscany, I decided to make an iris bed between the greengage trees in the glade beside the meadow.Iris Tuscany

The bed gets  plenty of sun from early morning to mid-afternoon. Digging it out and removing roots of perennial weeds took ages but the hard work was interspersed with dipping into books and catalogues to decide what to plant and where to go for them. Woottens of Wenhaston provided Jane Phillips, Souvenir de Mme Gaudichan and iris germanica. Peter Beales Roses had a lovely dwarf bearded iris called Hocus Pocus and in Diss  I found four pots of an iris germanica named Black Stallion. I plan to plant iris reticulata in amongst these to get some early blooms.New iris bed August 2016

Duckweed menace again 

After a year with hardly any duckweed (don’t ask me why) it’s back with a vengeance.

 There are 8 ducks apparently hoovering it up for hours every day, but neither they nor the grass carp, which also feed on duckweed, make much difference when there’s this much on the pond. In the right conditions, according to the books, duckweed can double in 3 days.

We clear it by the very simple method of putting on waders, getting into the pond, and pushing a long 6 inch plank held on edge through the water, so the weed piles up in front of it. Enough of the plank is submerged to trap the weed in large quantities.

imageWe push it to the bank and then scoop the thick accumulation of duckweed out with a grass rake, onto a large plastic sheet, allowing the water to drain back into the pond along with lots of tiny creatures. The plan is to reduce the duckweed to the point at which the ducks and fish can eat all the new growth andkeep it under control.

And here is the cleared pond. The green in the centre is the reflection of a bush in the clear water!

Surplus pond weeds as a mulch 

Lots of people say blanket and duck weed should be put on the compost heap. Just turned over a year old, well looked after heap, which has been banked up with earth and has plenty of soft material in it, so ideal composting conditions. We discovered none of the pond weeds had rotted. Not such a good idea after all.

However, we’ve increasingly used the pond weeds as mulches to keep the roots of plants damp and to wipe out weeds, and especially the reeds that are trying to conquer the edges of the pond again. So the pond is producing a useful product after all.