Building a Bog garden

If you have a pond in your garden, then a bog garden by it’s side adds another new and very useful dimension to the plants which you can grow.

A bog garden, once built, takes very little maintenance as most weeds will not grow well in the wet conditions. You do, however, need to be careful of the plants which you choose to grow as many are quite rampant and will take over the area very quickly, choking out other, more tender plants.

Building a bog garden is not difficult. It does not need a pond next to it as they do not share water, a pond as a neighbour just looks more natural and provides somewhere for any excess water.

Having decided on the size, shape and placing of your bog garden, the first thing to do is to dig a hole. This needs to be at least a foot deep. Then you line it with a plastic sheet. Make a few drainage holes in the plastic. You want the area to be very damp but not swampy. Then back fill it with soil. Any soil will do, although heavier soil such as the clay mixes are better. However I had a bog garden with rich loam in it and it worked well enough. If you are building your bog garden adjoining your pond, make sure the bog is higher than the water level to the pond. Again you want damp, not swamp.

The choice of plants for your bog garden is a very personal one. There are a great number of bog plants available, you will find the choice is greater in a shop which specialises in pond plants. Make sure that you are getting bog plants and not pond marginals. Pond marginal plants like their roots in shallow water whilst bog plants want their roots in wet soil.

Once you have built and planted your bog garden, there is very little else to do except sit back and enjoy. You may, from time to time want to cut back any plants which become to rampant and tidy any dead plant material. Also, if the weather is particularly dry, you may need to add water to keep the soil boggy. Then just enjoy, not just the plants but also the wild life which will also enjoy your bog garden.

Plants for your garden pond

The plants which you grow in and around your garden pond really rely upon your personal taste. That said, there are a few things you should know about water plants.

There are four types of pond plants, those which live on the surface (floating plants), deep-water plants, marginal plants and submerged oxygenators.

First, ponds need oxygen, particularly if you are keeping fish. So you need to have oxygenating plants. These are available from almost any retail outlet selling plants. They are not particularly decorative and live in the bottom of your pond, but they are necessary for a healthy pond. Do not buy too many, they will grow quite readily.

Deep water aquatic plants are those which root at the bottom of the pond but have leaves which float on the top. Water Lilies come into this category. These plants are not just highly decorative but they also are very useful in reducing the growth of algae which is what turns the water green in your pond. Algae live on mineral salts and sunlight so the more cover you have on the surface of the pond, the better. There are other plants which perform this function equally well, Water xcrowsfoot (Rununculus) looks attractive as well.

Floating plants also reduce the amount of sunlight which reaches the surface of the water. Some of these are not totally frost hardy, so you need to be aware of what you are getting. The most notable plants in this group are water hyacinth and water chestnut, though there are others.

The last group of plants, marginals, are the largest. These are plants which like their roots in shallow-ish water and their stems, leaves and flowers above water. This also covers those which like to grow in marshy soil (mud). There are so many that the mind boggles. You just choose the ones that appeal to you most.

One other thing, when you put water plants in pots,  you should not use ordinary garden soil or compost. This is too rich in minerals and will encourage the algae to grow. You can get special compost which has been depleted of minerals to do the job. You also need to use baskets rather than pots to plant in, so that the water can easily get to the roots of your plants.

Having buried your plant in its pot, put a layer of gravel on the top, this will help to stop the soil from washing away and protect the roots from foraging fish.

Edging your new garden pond

So now you have dug and lined your garden pond and the next thing to do is to put an edging in it. There is only on thing that you need to know about this and that is that the pond liner should be protected from direct sunlight.

If plastic or butyl liners are exposed to sun light, they will crack and no longer serve their purpose. It will shorten their life quite considerably, so when putting an edge on your pond, you should ensure that the liner is protected.

There are a number of ways you can edge a pond. You could do what is known as ‘hard landscaping’. You could put paving slabs along the edge. If you go for this route, you should overhang the paving slabs a few inches. This will cast shadow on your liner and therefore protect it. There are a lot of things going for paving slabs on the edge of your pond. It means you protect your shoes whilst walking on it. It needs no maintenance (except perhaps the occasional sweep – although even that will be taken care of by the wind eventually) and it can make a hard base for a seat.

There are other, more wild life friendly alternatives. You could have grass right up to the edge. You lift the grass and spread your excess liner under it, then lay the grass, on top. It will soon grow so that the edge is in the water and then it will grow rapidly, needing a cutting quite frequently to keep it looking anywhere near tidy. It provides a great habitat for all sorts of pond life and gives the pond a very natural look.

Another alternative is to plant flowers right up to the pond. If you want a naturakl look for your pond with a minimum of maintenance, these could be native, wild flowers. This will provide food and cover for loads of butterflies and dragonflies. You could plant your normal choice of decorative plants in a flower bed next to your pond. Or you could make a bog garden  allowing you to grow yet a different assortment of plants. I will talk about bog gardens another time. They are fairly simple to build and need very little maintence.

One other thing you could do is to make a small waterfall on one side of your pond. This will give you moving water, a lovely sound in the garden particularly on a hot summer’s day. A waterfall also helps to add extra oxygen into your pond, necessary if you are keeping fish in it and the weather gets hot and sunny. Again, I will talk about waterfalls at a later date.

There is one other thing, I should have mentioned earlier and that it that the sides of your pond should be level. The water level will show very clearly if it slopes and, unless you want it to look lop-sided, then you should ensure that the edge of the pond is level. This is not always easy but necessary. You will find it endlessly annoying if you have six inches of liner showing above the level of water at one end and the water is overflowing at the other end (Unless, of course, you have planned it that way.).

A Pond in your garden

Water in your garden adds a whole new dimension to the pleasure you derive from it. You can grow a number of plants which you would not otherwise be able to cultivate and the wildlife it attracts is endlessly fascinating. If you have moving water, the sound and look is very soothing.

If you do not have a stream in your garden (and most of us don’t), then the alternative it to build your own water feature. This could be a man-made stream or rill or a pond with, perhaps a water fall.

It is not difficult to make a pond. It is simply a hole which is made waterproof and filled up with water. Making one which fits your taste, is useful and safe to wildlife, and is able to sustain plants takes a bit more care and planning.

First, the size and shape of your pond. This is a matter of taste, how much room you have, and how much you can afford in the way of pond liners. Remember though, if you want to keep any fish – even goldfish- then it needs to be at least 2.5 feet deep. This is so that it does not freeze too much in the winter and get too hot in the summer. One other thing about siting your pond. Try not to put it under trees. The leaves will fall into the water and rot. This will make your pond smell nasty, it will also make the water toxic to plants and wildlife. If you want to grow ‘marginal’ plants in your pond, you will also need to build in a shelf 9 inches from the top. This can be around as much of the pond as you wish, but it is nice to leave a gently sloping area into the pond to allow any wildlife to come and drink from your pond without falling in. It will also allow any creatures which do fall in  to get out. If you cannot build in a slope, then add a stick or branch which they can climb on to get out. There are a number of fatalities among hedgehogs particularly because they fall into garden ponds and exhaust themselves trying to get out, eventually dying.

After you have decided on the size and shape of your pond, mark it out with string and leave it for a week so that you can make sure that is exactly what you want. Then just dig it. Make the sides slope slightly outwards from the centre, it will make it more stable. Next comes the lining.

In order to have a pond you need to keep water in it. This means a waterproof lining of some kind. You could put in six inches of fullers earth. This makes it very natural. It also makes it very hard work and very expensive, and not necessarily permanent. You could concrete the bottom and sides. Again, it’s hard work and you need to ensure that the chemicals in the concrete do not leach into the pond and upset the balance of the water. The other, much easier, much less expensive way is to you a plastic liner.

Basically, there are two types of plastic liner you can buy. The first is made of butyl, it is quite thick and therefore is hard wearing. It is usually guaranteed for up to 20 years. The less expensive alternative is a plastic liner. These work very well. However, they only last about five years and will then need to be removed and replaced. A nuisance if you have a lovely looking, settled pond.

Working out how much liner you will need is quite easy.  First you measure the depth. Make a note of this size , you will need it. Next measure the longest part of your pond, add the twice the depth of your pond. This is the length of liner you need. The width is much the same, measure the widest part of your proposed pond and add twice the depth. It works like this: If your pond is going tobe 3 feet long, 1 fot wide and 2 feet deep, then the liner will need to be at least 3 ft plus 1 ft plus 1 ft long and 2 ft plus 1 fot plus 1 fot wide. Furthermore, you could really use a litte overhang, so that it can be anchored at the edges by waterever you are edging your pond with. I will talk about this at a later time.

If you have a stony soil, you should put a thick lining to protect the plastic from being cut by the stones (even if you don.t have a particularly stony soil, it is still as well to do this). You can do this by either laying two inches or so of sand and then laying your liner on it, or line it with something else which is thick and will resist stones. Old carpet it ideal. Then lay your liner, making sure there are no folds or wrinkles in it. Anchor the sides, the liner will move inwards as it fills up with water, but allow some movement as you don’t want it hanging above the ground at the bottom. Fill it with water and voila, you have a pond ready for plants, fish or whatever else you want to do with it.