Table of contents:
- What is groundwater?
- Types of groundwater
- How to determine the level of groundwater in your area yourself?
- Improving the soil - building a drainage reservoir
- We equip drainage channels in the future garden
- Improving soil composition
- Rules for planting seedlings in an area with high groundwater
Video: Site With High Groundwater. What To Do? Defining, Drainage, What To Plant
Groundwater can pass under each site, be a small accumulation or a whole rivulet, and we will calmly grow a garden and never know about them. But this is only if they go deep enough. What should a gardener do, whose groundwater reaches almost to the very surface of the soil, really fold his hands and just abandon the site? Today we will talk about how to determine the presence and level of groundwater as accurately as possible, what and how can be planted on such a site.
What is groundwater?
By its nature, groundwater is ordinary water, which sometimes accumulates in deeper and sometimes in shallower soil layers. It can be moving or standing (that is, motionless, in the form of a lake under your site). They form, that is, they create such water showers, and sometimes a large amount of snow. It seems to you that the moisture has been absorbed and gone, but in reality it can collect in the soil, increasing every season. In addition, the so-called "condensate of water vapor" forms underground waters, which itself is formed in the ground and, alas, we cannot influence its formation.
Of course, first of all, the depth of the groundwater location depends on the relief of your site, as well as on the presence or absence of rivers and streams, that is, water bodies near your summer cottage or home. Where the soil is swampy or in the lowest regions, groundwater is almost always on the surface of the soil; it often rises above half a meter from the surface and rarely falls below one meter.
Types of groundwater
Few people know that the level of groundwater can vary significantly even during the same year. Usually, this level reaches its minimum values in winter, when the soil completely freezes and is inaccessible for water penetration. In the spring, when abundant snowmelt begins, the level of groundwater rises, because the soil during this period is literally oversaturated with moisture, and moisture in such a significant volume serves as a source of saturation of groundwater.
Often a pair of types of groundwater is considered - verkhovodka, that is, the so-called local groundwater and free-flow, that is, external groundwater.
The first one usually occurs at depths from half a meter to three meters and can be located in sections, often in significant depressions or between soil layers. Interestingly, in a drought, for example, at the height of summer or too frosty in winter, the perch may disappear partially or completely. Naturally, as soon as it rains again, or the snow begins to melt, that is, the moisture content of the soil rises, the top water will return to its original place.
If we identify the composition of the water of the upper water, it turns out that there it is usually fresh with a minimum presence of minerals and is even toxic to plants.
The second option is free-flow water, they can lie at a depth of one meter to five, and often this is a constant phenomenon, from which the gardener cannot get away. It is these waters that give gardeners the main inconvenience, since they are replenished by melting snow, rain, if there is a lake, river, rivulet or even a stream nearby (as mentioned above). They can feed free-flow water and artesian wells, as well as condensate, which we have already written about.
How to determine the level of groundwater in your area yourself?
First, you need to choose the right time to determine the groundwater level at the site. It is early spring, usually at this time the groundwater reaches its maximum.
You can determine the level of groundwater visually, just go to a nearby well and look inside, if it is dry, then the groundwater is located deep and there is no danger, you can plant, and if the well is full of water, then this should alert. Usually, water can come to a well from some underground source. The distance from the water mirror to the surface of the soil can be determined by lowering a tape measure or twine there.
Another option for determining the level of groundwater occurrence is by the plants that grow in this area. For example, the site looks completely dry, but if it is covered with lush vegetation that adores moisture and it grows violently and luxuriantly, then most likely the groundwater is lurking somewhere close to the surface.
For example, nettle, sedge, hemlock, reed, digitalis and similar plants growing on the site should alert you. In this case, the maximum occurrence of the groundwater level will be equal to two meters (but this is in the best case).
If wormwood or licorice "spikes" on the site, then you can breathe calmly: most likely, there are three meters to the groundwater, and on this site you can plant anything you like, well, with the exception of walnuts and Manchurian nuts.
You can notice the close standing of groundwater and the color of the plants growing in this area, where they will be as juicy and bright green as possible, without the slightest hint of a lack of moisture in the soil.
Various midges will also help determine the level of groundwater in the area: if midges swirl and curl over the same area every day, then the water is very close. Even cats, relieving themselves, usually choose the places of intersection of water veins, but dogs, on the contrary, go to rest in areas with the highest possible groundwater level. If the groundwater is close, then in this area you will not see an anthill, wormhole or mouse hole.
Pay attention to the site in the evening, if fog spreads over it, then the groundwater is as close as possible to the surface, and two meters in this case will be the limit. Also, in areas with a close standing of groundwater, dew accumulates more actively and in a significantly greater amount.
Of course, if you want to know the level of the groundwater location as accurately as possible, you will have to dig a hole or drill a well. The latter costs money, but then you don't have to spend personal time and effort digging a possibly very deep hole. The drill will definitely tell you, to the nearest centimeter, the level of the groundwater. And then you can watch the remaining well: if it doesn't fill up with water, then everything is fine.
If you decide to plant plants on soils with a high level of groundwater, then plant shrubs and pome crops, necessarily grafted onto dwarf rootstocks, because their root system lies close to the soil surface and even one meter of dry land may be enough for them.
But all the same, before laying a garden of pome plants on dwarf rootstocks and shrubs, on soils with a high standing of groundwater, it is imperative to do a number of measures in order to minimize the risk of plant death.
Improving the soil - building a drainage reservoir
If the groundwater level in your area has passed the meter mark or part of the soil is simply swampy, then you can build a structure for the outflow of excess moisture - a drainage reservoir. To do this, remove the grooves from the site, cover them with plastic wrap and make sure that water flows down the grooves into one pre-selected place, it should be as low as possible. Then there is a chance that groundwater will gradually leave your site, forming no longer underground, but an external lake or swamp. In the future, the surface of the future reservoir itself will draw water from the soil due to the active evaporation of moisture from its mirror, which means that the larger the reservoir in area, the more part of the site you can bring back to normal.
We equip drainage channels in the future garden
Drainage canals need a whole network, they must literally encircle the site, you can even throw bridges over these canals and move along them to the main place, which will gradually drain.
Before constructing drainage channels, you need to determine in which direction your site is leaning. After determining, try to make sure that the channels are directed exactly in the direction of the slope. After digging them, be sure to lay them all out with a thick plastic wrap, it will protect the channels from overgrowing. Ultimately, all the channels should converge in one place, forming something like a pond that will serve as an evaporator of excess moisture. It will be possible to draw water from it for irrigation.
In the event that it is not possible to build a drainage pond, then make at least a drainage well, also directing all the channels from the site into it. But in this case, you will have to use a pump, which from time to time will need to pump out water from the site, draining the well.
Improving soil composition
Soil with a close groundwater table, and even more so swampy soil, is usually quite poor, and if you manage to dry it, you will still have to improve it before you plant plants in this area. In addition, the soil must be checked for pH level: it is possible that the soil on the site is highly acidic. Then, before winter, you will need to add from 300 to 400 g of lime per square meter or the same amount of chalk, dig everything thoroughly, and in the spring measure the pH level again, and do this until the soil becomes neutral.
Further, ideally, on top of the existing soil, you need to pour imported soil. Thus, you will raise the site and increase its fertility.
Further, the site needs to be dug up by mixing the soil and adding dolomite flour in the amount of 300 g per one hundred square meters of land. Before planting seedlings (if planting is in the spring, then autumn fertilization is just ideal), you need to apply 250-300 g of wood ash per square meter, a bucket of humus and a teaspoon each with a pea of superphosphate and potassium sulfate (all this is for digging, even if you have to dig up the site again).
Rules for planting seedlings in an area with high groundwater
We must say right away that you should not rely solely on imported soil. Yes, it will raise the site and drainage channels will also improve the general condition of the soil, however, for the full growth of fruit trees (berry bushes can be planted safely), this may still be not enough.
In this case, the planting of both pome and stone fruit crops should be carried out not in traditional and well-known pits, but on improvised mounds that can reach a height of a meter, depending on the rootstock on which the seedling is grafted: a dwarf means the height of the mound should be equal to one meter, a superdwarf - which means that half a meter is enough.
But you still cannot do without deepening, the root system of the seedling must be fixed. To do this, you need to remove a layer of soil to a depth of about three tens of centimeters, and a diameter of 35-40% more than the volume of the root system.
It is in this depression that you need to pour a mound of soil, as nutritious as possible. It is great if it consists of fresh soil, well-rotted manure or compost, as well as 200 g of wood ash and a teaspoon of potassium sulfate.
After that, the seedling must be planted on this mound, having made a depression sufficient to accommodate the root system so that the roots do not stick out from the mound in different directions.
The rules for planting, that on the mound, that in the planting hole are the same - you need to focus on the place of transition of the roots into the trunk, that is, on the location of the root collar. This very root collar should in no case be buried: in stone fruit crops it should stick out 2-3 cm higher than the height of the mound, as if rising above it, in pome crops you can even push it a couple of centimeters higher. The fact is that when the root collar of pome crops is deepened, there is a strong lag in development and the fruiting period begins much later, in stone fruit crops, the deepening of the root collar can even lead to its aging, especially if the soil in the future is partially waterlogged - inept and frequent watering or rains, then the tree will simply die in the end.
That's all that I wanted to tell you about groundwater, how to determine their level on the site and what and how you can plant. If you still have questions or if you want to share your personal experience of planting plants in such areas, then write about it in the comments.