Pond – maintenance and wildlife
I may have mentioned in my earlier pieces about creating the pond how certain plants overwhelm the space allotted (and indeed every other space) and have to be removed completely – I’m thinking Typha minima here particularly – but it is staggering to me how vigorous waterplants are in their growth when you think they are either freefloating in just water, or anchored into very very poor soil in the margins.
The aim with the new pond was to eventually reach a balance of oxygenation, foliage cover and plant growth such that the water would remain clear all year. I expected from the literature I had read that this would take three years to achieve – partly due to the water settling down after all the nutrients had been put into it as I put the sieved sub-soil in for the marginal to be planted in, and partly due to the plants put in to cover the surface growing to the right size. To begin with I had only two small bits of Water Soldier, Stratiotes aloides, and they took a couple of years to begin spreading, during which time the broad leaves of the Water Hawthorn, Aponogeton distachyos, were the main foliage covering the pond at the other end. See how well the Water Soldiers are doing now – here beginning to rise in early May last year:-
And here is the Water Hawthorn in early July 2013, with Acorus gramineus ‘Variegatus’ overhanging its broad leaves which are being used by Blue Damselflies to lay their eggs under:-
However, I think the pond is too small and still to escape getting algal bloom in very hot weather, especially this past year with the extremely hot summer, and the blanket weed has to be fished out regularly once the water heats up, even after 9 years. But apart from keeping on top of unwelcome plants like blanket weed and duck weed making appearances, the invited plants need to be kept on top of too as they grow rampantly (like the Water Mint, Mentha aquatica, and the Parrots Feather, Myriophyllum aquaticum). Even more polite pond plants spread or seed themselves around too much – see the shot below across the pond to the bog garden, also in May last year:-
The Caltha Palustris in the foreground, and on the beach area along the front of the pond to the right are self seeders from the original patch in the back corner. The Iris - Iris pseudacorus ‘Variegata’ – you can see in picture are all seedlings from the patch in the left hand corner of the pond, and as you can see many of them are coming up plain green. Even the Equisetum hyemale you can see top left is not where it should be – this is more than 60cm past its original planting spot and working its way through the Caltha Palustris AGAIN, even though each year at least once it is removed from this area…
Whilst cutting back dead leaves and removing any that fall into the pond to keep the nutrient level of the water as low as possible to mitigate against blanket weed is a continuous process, it is always a struggle for me to find the right moment to do a big pond tidy up, avoiding both serious injury to lots of our pond wildlife during critical points in their life cycle, and the freezing weather in winter which makes having your hands in the water extremely unpleasant. Here are some pictures of once such operation in February 2017. Here is the pond before starting:-
You can see how the Equisetum hyemale is not just growing completely along the left hand length of the pond, but is also all along the side at the front of the photo. Imagine if you will that it is SUPPOSED to be a clump in the middle of the left hand length of the pond with an Iris pseudacorus ‘Variegata’ nearest to you, and the Calthus Palustris at the far end, with some Acorus gramineus ‘Variegata’ between it and the Equisetum. Top right you may be able to see the Gunnera bed with the old brown leaves covering the crown of the Gunnera manicata.
To help mitigate the freezing cold water, I have now invested in what I describe as “waders for the arms” – long gauntlet pond gloves, which are good for grabbing lumps of things under water, but are not so good for detailed work, like trying to pull each stem of Equisetum out individually.
Here are the gloves in action – pulling out mainly Water Soldiers, Mentha Aquatica, Parrots feather, and iris leaves by the look of it :-
Here is a shot of some of the piles pulled out, including the Equisetum hyemale, showing the clump brought under SOME control:-
Here is the pond after I’ve taken all that material out, as I gradually remove the piles of detritus to the compost heap – having left them for a while for any little animals to crawl back into the pond:-
Here is the same shot a month later with the Water Soldiers submerged:-
The Marsh Marigold leaves just beginning to break:-
And the Equisetum hyemale looking good:-
In the corner the Iris is planted in the frog spawn is laid as usual – the Iris have made a sort of shallow bowl as you can see below and the frogs lay their spawn on top of the Iris corms which I presume helps to protect spawn and tadpoles from predators in the pond:-
Here they are hatched less than two weeks later – as you can see they stay put protected by the mass of jelly they hatched out of when they are very small:-
I am mindful that you want to hear about my hardy perennial plants rather than the wildlife they attract, but the pond is a very wildlife-dense area of any garden, and I chose marginal and water plants I thought would help encourage wildlife as well as looking good. Apart from bringing a frog and a toad in the green “washing up bowl” pond from our tiny London home as I mentioned previously, all the other wildlife came to our pond of its own accord. Indeed, as we were digging the pond hole a male Emperor Dragonfly appeared and buzzed round us, our first sighting of one here. I chose as many native plants as I could, especially ones that dragonfly and damselfly larva could climb up stiff stems in the water to turn into their adult forms, and for them to perch on as adults to hunt for food. Also ones that had leaves they could rest on to lay their eggs under, as shown above with the Water Hawthorn leaves. I believe in previous months' articles about the pond I have shown you the dragonfly exuvia (their larval “skin” that they shed when becoming adult dragonflies) on the Mentha aquatica leaves, and the adults resting on the Equisetum hyemale. As you will have noticed from many of the photos in the other articles I wrote about developing our pond we have both red and blue damselflies developing in our pond, as well as mayflies and several species of dragonfly. Here is a blue damselfly on the seed head of Caltha Palustris, with Water Soldier leaves behind :-
Here is a female Broad Bodied Chaser Dragonfly resting on the Escallonia 'Donard Seedling' in June last year (The male has a blue tail making their sex easy to tell apart):-
In the pond I have two sorts of pond snails – ones that look like tiny winkles, and ones that look like ammonites:-
You may be able to tell how small they are if I tell you that the brown seed in the top left of the first picture of snails is from the Iris pseudacorus ‘Variegata’.
Here are two tiny bugs that live on the surface of the water – the Common Pondskater, Gerris lacustris:-
And the Whirligig Beetle (Gyrinus natator) – the whirlpool effect is one the beetle generates itself :-
To finish with a more decorative hardy plant picture - another plant that has self-seeded itself into the pond, this time from the bog garden rather than just expanding round the margins, is Purple Loosestrife, Lythrum salicaria. This surprised me as I assumed it would not like to be in water all the time, but it set itself in the Watermint (Mentha aquatica) pot in the pond margin three years ago, and has not only thrived but expanded slightly last year. Below you can see the original selfseeder with some spikes in full flower centrally, and perhaps note its younger seedlings growing through the Iris leaves? (Already in late June 18 there was no water visible in the pond due to the heatwave):-
Next month, some of my boundary plants, and another winter job – pruning and tying them into frameworks.