It is a mistake to believe that if cacti are succulents and their natural habitat is not very favorable, then there is no need to take special care of the soil.
Not only should the earth be nutritious and enriched with microelements, it is also individual for each group of cacti, which are desert, forest. Therefore, the soil for cacti should be selected as similar in composition to the one in which they grow in nature. However, in practice, these plants are grown using mixtures based on universal primers, which are often compiled empirically.
Soil composition for cacti
Desert cacti, as well as species with turnip roots, prefer clayey cloddy soil, while forest and species with a fibrous root system prefer loose soil. But in any case, the soil must be air- and moisture-permeable, with low level Ph (not higher than 6.5). At the same time, fertilizers should not be included in the composition of the soil, since cacti do not need additional substances that stimulate rapid growth, minerals, in particular, a high nitrogen content.
Types of cacti prone to decay, such as Ariocarpus, Strombocactus, Blossfeldia, are grown in permeable soil with a lot of stones.
Species with spines need more calcium than species without spines. Therefore, it is advisable to add eggshells crushed into dust into the soil.
To retain moisture, soddy land is needed (clay, but black soil is not recommended). Leafy earth is rich in nutrients, charcoal is an antiseptic, prevents the appearance of rot, is added in the form of pieces, and wood ash, dolomite flour reduces soil acidity.
Lime is added only to the soil for cacti that need it, such as astrophytums and other species with long spines.
Coarse-grained sand (river or building sand), sifted brick chips, expanded clay, pebbles, sifted and washed from dust give the soil additional friability and breathability small sizes, crushed stone, vermiculite. The listed components, with the exception of sand, should be selected depending on the size and age of the cacti. For example, for young plants, seedlings, it is better to use a small fraction, and for adults - a large one. Before preparing the soil, all components are sterilized.
How to make soil for cacti
The soil for desert species should consist of equal parts of turf, leaf soil, peat and coarse sand.
A different soil composition is needed for lowland cacti, which includes the huge genus of Echinopsis. The soil mixture must be porous and nutritious, and may consist of:
2 parts turf land
1 part leaf soil
1 part peat
1 part humus
1 part coarse sand
Very fertile soil is necessary for cacti of the Cereus family, which are characterized by rapid growth and large size.
1 part turf soil
1 part leaf soil
1 part peat
1/4 humus
Based on the finished soil mixture, they make up simple soils for unpretentious cacti:
2 parts prepared soil
2 parts coarse sand
1 part gravel
When planting, a drainage layer of expanded clay or crushed stone is placed on the bottom of the pot, then soil is poured, and another layer of expanded clay or pebbles is placed on top to prevent rotting of the root collar. But top drainage is not always used, because it makes it difficult to control soil moisture.
Ready soil for cacti
When choosing a universal ready-made soil for cacti, you should carefully study the composition, which should contain turf and leaf soil, humus and (or) high-moor peat, and coarse sand. It is possible to contain vermicompost, but such nutritious soil is added in small quantities. Other components of the composition are dolomite flour, charcoal, wood ash.
The most popular ready-made soils include Vermion soil, enriched with vermicompost, as well as the “Flower Happiness” soil mixture with the addition of dolomite flour, “Tropic for Cacti” by Fusco.
Special soil purchased at the store requires the addition of certain components, depending on the type of cactus.
The main trouble of novice cactus growers, as a rule, is that, paying close attention to the composition of the earthen mixture - so much sand, so much clay, so much rotted leafy earth and peat chips - they forget about such an important thing, like soil structure. And cacti are very demanding of it.
Cacti need rough and loose soil. This is achieved by an admixture of gravel, coarse river sand, vermiculite mulch (loosening granules various shapes), etc. The soil for cacti should be coarse-grained and loose, well-permeable to air and water, and not contain any organic fertilizers like manure, bird droppings or horn sawdust.
The ban on such components is explained by the fact that all organic fertilizers are very rich in nitrogen, but in cacti the need for it is extremely limited due to some physiological characteristics. Even a slight excess of nitrogen leads to undesirable and often dangerous changes in the normal development of the plant: its stem begins to quickly stretch, loosen, and become watery. The hairs and thorns weaken, the skin, which cannot keep up with the growth of the swelling stem, bursts, and ugly wounds and scars appear on it. Such plants lose their resistance and die easily, becoming victims of pests and any fungal infection.
The soil, of course, should not contain harmful substances, pests, disease germs and undecomposed organic matter. According to its structure, it needs to remain loose long time. Permeability is also important because cacti cannot tolerate the soil being loosened and dug up. It must also be sufficiently nutritious (it should be remembered that sufficient nutritional value from the point of view of cacti and from the point of view of, for example, fuchsia are different things). It is best to use a mixture that contains leaf humus, clay-turf soil and coarse river sand with crushed stone in any proportions that suit you. Here is the approximate composition of a universal mixture that is used in many collections:
2 parts (by volume) of leaf humus without twigs and knots;
- 2 parts of clay-turf soil, in lumps, without grass and roots;
- 2 parts of river sand, well washed to remove dust;
- 1 part charcoal and brick (equal parts), crushed and sifted from dust.
For 3.5 liters of this mixture add one teaspoon of crushed chalk or eggshells(that is, calcium carbonate, essentially), a handful of vermiculite mulch and one teaspoon of superphosphate.
By the way, there is a ready-made soil mixture on sale called: “Cactus soil.” It is intended for breeding such species as zygotocacti, epiphyllum, aporocactus, echinopsis, rebutia, parody, pseudolobivia, etc. The soil is optimal in acidity and is best suited for breeding the above plant species. Packaging volume - 2.5 l, 5 l. Hazard class - 4 (safe). This mixture has proven itself well and only requires the addition of a leavening agent (sand, expanded clay or brick chips). On the packaging of ready-made mixtures it is always written what groups of cacti it is suitable for. this option, since they are designed taking into account the requirements various groups plants.
Four-fifths of all cactus species will grow well in an all-purpose cactus mixture. And only the remaining one-fifth will need soil that meets its special requirements - either devoid of natural nutrients and structural elements, or enriched with them. As a rule, we are talking about the addition of clay (especially for nodule species), lime (for example, Cephalocereus senilis) or humus soil (primarily for epiphytic species). To achieve water permeability and looseness of the soil, it is necessary to add to it, as already mentioned, sand, brick chips or peat in such an amount that these substances make up at least two-fifths, and maybe even half or a little more of the earth mixture.
It would be useful to dwell in a little more detail on the role and significance of each of components earthen mixture.
Crushed brick and peat in its composition it plays a double role: pieces of it, embedded in the ground, make it more porous - this is the first thing. The second, most important purpose of both brick and peat is to serve as a soil moisture regulator. The fact is that these substances are very hygroscopic and therefore can absorb excess water during watering, slowly releasing it to the soil as it dries.
In terms of improvement physical properties land for cacti, these most commonly used structural substances are almost equivalent. Both brick chips and peat improve the soil due to their chemical effects. Both sand and brick chips can be used separately and in any combination with peat. At the same time, in combination they help neutralize the influence of their negative aspects. For example, brick chips not only loosen the soil, but also exceptionally maintain uniform moisture in it, disintegrating into dust after a few years, which contributes to its caking. Too sandy soil becomes light very quickly and dries out quickly. Peat, which supports the formation of roots in a plant, in case of an overdose can have an unfavorable chemical effect on the roots of some “capricious” species after some time.
In the above combination, you can use ground and washed expanded clay or crushed stone with a grain size of 3-4 mm as a substitute. In an open-air culture, a smaller amount of these substances is sufficient than in a window culture. Finally, in a stuffy, humid greenhouse, they can make up half the cactus mixture. It is important that all these substances are clean and sterile. In addition, the brick chips must be sifted and washed so that they do not contain dust. Its grain size should be 3-5 mm.
Modern vermiculite mulches can be used as a loosening component. These are porous granules in the form of grains, flakes, etc. They regulate soil moisture and air permeability. Sold in flower shops.
Coarse sand. In cactus culture, this concept means river sand. It should be as coarse-grained as possible. Sand, previously washed clean in running water, is very important for giving the earth mixture the necessary looseness and porosity. If you use sea sand, it should not only be washed, but also kept for a long time in a container with fresh, frequently replaced water.
Cacti will grow well in clean brick chips if you add the necessary nutrients dissolved in water for irrigation. They can be added to every cactus mixture. Sometimes in this soil plants do not develop as we would like. But the point here may not be in the soil, but in diseases or pests that the cactus grower is not even aware of.
Leaf humus, that is, leaf soil, has several properties important for cacti, and it is very difficult to replace it with any other. First of all, it is rich in nutrients in already processed soil bacteria form available for absorption by the plant. In addition, it is loose, light soil that absorbs water well, which is very important for cacti. It dries out much faster than clay, thereby preventing dangerous stagnation of water in the pot.
Will the organic, nutritious part of the cactus soil consist of leaf soil from the forest or a mixture of soil from various sources? The main condition is, first of all, the soil is healthy and clean. If you take it from the garden or vegetable garden, you should prefer the one that was fertilized three years ago, no later, and where legumes grew last year. As for forest humus, then, perhaps, beech leaf soil is best suited. Forest humus soil is loose and moderately fertile, but it can be so light that it can only be used in a mixture with clay soil. To do this, it is best to take soil from molehills on pastures - it has good breathability.
Clay soil firmly retains water and nutrient salts dissolved in it. Its lumps can be compared to tiny storehouses, releasing nutrition much more slowly than other soils. The viscosity and density of clay soil is especially important when planting tall or large cacti, as it helps the roots better support the significant weight of the stem. But the admixture of dusty clay soil is extremely dangerous - it cements the soil.
The degree of looseness can be accurately determined by squeezing the soil in your fist. During this test, the fresh cactus mixture should remain in a lump, but with stronger compression it should crumble. If light compression does not form a soft lump, it means the soil is too loose, sandy or dry. Very heavy, clayey or wet soil remains in the lump. In the first case, you need to add clay, and in the second - sand, brick chips or peat. For epiphytic species, add light soil, but rich in humus and nutrients. Plants with turnip roots need heavier soil; you can add a little more clay to it. But sand is also necessary - for sufficient permeability.
Charcoal and sulfur powder have anti-rot properties, which are very valuable in the culture of easily rotting cacti. In addition, they, like sand, contribute to soil looseness. For a liter of cactus mixture, you can add a little charcoal in the form of fine crumbs and a spoonful of sulfur powder, also a very good antiseptic.
Superphosphate not only enriches the soil with phosphorus, but also slightly acidifies it, which is very useful for cacti.
Lime Our plants need it not only for the formation of spines, hairs and bristles, but also for correct exchange substances that help normal absorption of nutrients. This component is added in larger quantities for some “lime-loving” species, such as astrophytums and a number of white mamillaria. Lime is added to the soil in the form of crushed chalk, eggshells, and shells.
The degree of acidity or alkalinity of the soil is usually indicated on the pH scale, indicating the concentration of hydrogen ions: pH less than 7 - acidic soil reaction; A pH of 7 is a neutral reaction; pH greater than 7 is an alkaline reaction.
Most cacti grow well in moderately acidic or neutral soil. As a result of constantly watering plants with hard water from a well or water supply, the soil becomes more and more alkaline, so it is necessary to update it from time to time.
The roots of cacti are so sensitive to soil alkalinity that already at pH = 7.5 the growth of most species stops, and at pH = 8-8.5 almost all of them die. Based on the results of observations, it was noted that cacti feel best in soil whose acidity is 5.5-6.
It must also be said that excess lime in the soil not only interferes with the growth and development of cacti, but also spoils them appearance, deposited on the lower part of the stem in the form of a dull yellowish-gray crust. At first, this crust is easy to remove with a soft brush - it is thin and fragile, and when touched, it falls off like a shell. But the longer this calcareous crust remains on the stem, the more difficult it is to remove. It seems to grow to it, eats away, and after removal, dark, dead spots remain on the skin of the plant, extremely ugly and rotting at the slightest damage.
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For a novice gardener, it is important to clearly understand what soil to plant the cactus in. Often such understanding comes after a series of trials and failures. You should not believe rumors that the most suitable mixture is the one that is similar to the composition of the soil in the homeland of cacti.
Some people plant the plant in completely unsuitable soil. At the same time, the cacti feel great. However, this does not mean that you can give up on the composition of the soil for the cactus. Special attention should not be given to it, but to the structure of the mixture, acidity, ratio and amount of nutrients.
Soil composition for cactus
To properly prepare a soil mixture for a cactus, you need to know some factors. For example, the plant variety, its age. The recipes offered by flower growers differ only in the combination of ingredients. But they always remain the same.
Before looking for the required soil composition for a cactus, you should know that it must meet two parameters:
- the mixture is chosen to be loose, easily permeable to water and air;
- low soil acidity.
To understand what kind of soil a cactus needs, its age is first determined. For young and mature plants, a loose, nutritious mixture is more suitable. That's why most The composition is made up of leafy soil. Adult and old cacti need dense soil. It will become greenhouse and clay-turf soil.
Plants growing in steppes and forests are usually planted in soil with a slightly acidic reaction. But mountain and desert prefer soil with a neutral reaction. The main ingredients of soil mixtures are leafy, old greenhouse soil, rotted manure, baked clay, and charcoal.
What kind of soil a cactus likes depends on its type. For example, plants that have virtually no thorns prefer mixtures without calcium content. But if the cactus is all decorated with spines, then even eggshells are added to the soil.
The optimal time for preparing the mixture is a month before planting. It is recommended to store it in a slightly damp state. It is very difficult to guess how a plant will react to a particular type of mixture. To identify the disadvantages and advantages, it is better not to change it for a long time.
Changes in the soil mixture can be detected during replanting by examining the root system. If she is developed and healthy, then the mixture is suitable. When the roots are rotten and have not developed enough, it is better to replace the mixture, since it does not bring any benefit.
Thus, the optimal soil composition for a cactus is determined by selection during its cultivation.
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Denis Davydov 02/6/2014 | 2429
Ready soils for cacti, sold in flower shops, are not suitable for all types, since their main component is peat. As a result, most cacti quickly lose their roots. In addition, such substrates are more suitable for growing epiphytic forest cacti, but not desert and mountain species. This is why it is best to prepare earthen mixtures yourself.
For standard and universal soil mixtures, I would recommend the following components.
Soil types
Clay-turf soil. It is easy to find in floodplain meadows, parks and near ponds. It is light brown in color, heavy in structure, quite moisture-absorbing, retains its properties for a long time, dries slowly and is very nutritious in microelement composition.
Leaf soil. It can be collected in parks and groves, deciduous forests, and gardens. It has a distinct black color because it is a product of leaf decomposition and is very rich in humus. Light in structure, nutritious, wets and dries well, virtually does not cake.
Coarse sand and fine gravel. The sand must be washed, not contain silt (small dust-like particles), have coarse-grained fractions and not produce turbidity when lowered into water. Such sand can be found on the shallows of rivers and reservoirs or in quarries. Ordinary construction sand is not suitable; it is, as a rule, fine in structure, will “cement” the soil without promoting its aeration, and also contains lime, which is unacceptable for cultivating most plants in general.
Mineral components. Promotes aeration and water permeability of the soil. Besides sand, the most common mineral components are brick chips, finely granulated expanded clay, vermiculite, perlite and crushed charcoal, which can be collected from extinguished fire pits. Charcoal intended for barbecue is not suitable, because... it is obtained by firing without oxygen and contains a lot of unburned and harmful resins.
Composition and processing of the mixture
To prepare a universal soil mixture for cacti, I use two parts each of turf and leaf soil, three parts of coarse sand or gravel, and one part each broken bricks, expanded clay and charcoal. To increase the nutritional value of such a substrate, you can add 1 tbsp. l. simple superphosphate per 3 liters of mixture. Cacti have little need for nitrogen fertilizers. Potash fertilizers can be applied as needed along with irrigation water.
For cacti from mountainous areas and arid regions that have a turnip-like root system, the amount of mineral components must be increased to 60-70% of the total volume of the mixture.
The “cactus” earth mixture prepared in this way should be slightly acidic, loose, air- and water-permeable and slightly moist. When you squeeze a small amount of this mixture in your hand, it should stick together and crumble easily with the slightest pressure.
An important aspect is the disinfection of the prepared mixture. This is achieved by steaming it for an hour in the oven, or processing it for 15-20 minutes. V microwave oven at a power of 440-600 W. Once the soil has cooled, it can be used for planting and replanting cacti.
From experience:
- For some types of cacti, a number of adjustments must be made to the original soil mixture. So, for species with turnip-shaped roots, the soil should be heavier; more clay-turf soil or a little pure lumpy clay should be added to it.
- For Mexican species that grow on limestone in nature, chalk or marble chips are added to the soil mixture. Due to processes occurring in the soil, these components will gradually turn into a soluble state and thus be absorbed by plant roots. Let me remind you that calcium and magnesium are needed by white-haired species, cacti with specks and strong spines for the formation of spines, bristles and hairs.
- Epiphytic cacti need more nutritious soil. For them, add 1 part of humus to the soil mixture or prepare a soil mixture with a smaller amount of mineral components and completely exclude calcium-magnesium components.
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It is common knowledge that the main factors ensuring normal growth and flowering of cacti are illumination, temperature regime, irrigation regime and composition of the soil mixture. Moreover the soil often plays almost a decisive role, since it not only provides nutrition to the plant, but also regulates the temperature, humidity and aeration of the entire underground part of the plant.
Thus, attempts to grow desert cacti in a temperate climate in soil taken from the yard can end extremely unsuccessfully: a cool winter in dense, slowly drying soil leads to the complete death of the roots and rotting of the root collar. When the mechanical structure of the soil is disturbed, changes in many physiological processes occur, which lead to weakening and even death of the plant.
The supply of water to the roots should always prevent its stagnation in the container and excessive moisture in the earthen clod. Free access of oxygen to the roots not only promotes the normal functioning of plant tissues, but also suppresses the development of pathogenic bacteria in the soil.
Cactus growers, from the point of view of approach to soil composition, are divided into two camps. One is made up of those who recognize traditional soil, the other - defenders of hydroponics. In the “soil-phile” camp there are adherents of leaf soil, chernozem, peat, and turf soil with many transitional stages. There are recipes for mixtures various types cacti.
Chemoculture
Owners of large collections and greenhouses specializing in growing cacti for sale prefer the so-called chemoculture- a type of hydroponics, which is the cultivation of cacti in a substrate that practically does not contain nutrients, with watering with nutrient solutions and subsequent, almost complete drying. Is this a surrogate, or is it progress?
Of course, for giant greenhouses maintained by a few workers, this is the only acceptable way. However, owners of small collections, which are the majority of cactus growers, encounter a number of problems. Let's try to analyze what causes this.
The substrate for growing cacti must meet the following requirements:
1. Should be moderately cheap and easy to obtain.
2. Must be permeable, especially in upper layers. This reduces losses caused by root rotting and simultaneously prevents the formation of algae deposits. This coating is unpleasant in appearance and makes it difficult for air and moisture to reach the roots.
3. Must consist of material that repels pests and pathogens.
These requirements certainly meet The substrate is purely mineral.
Many years ago, I switched to growing all my cacti in clean sand with brick chips, and was pleased with the results, especially in terms of root development. However, after three years I returned all the cacti to the soil mixture.
There are several reasons. It is necessary to have pans that do not leak. The tray must contain pots of the same size, otherwise they will dry out. different time, and watering can only be done at the same time. The cacti should be approximately the same size, again to allow the substrate to dry out at the same time. Different cacti are in different phases of development, some need nitrogen, others potassium, others phosphorus, and others generally need to be dried! The trays must be completely filled with pots, otherwise a large volume of nutrient solution is needed. And the pallets on the windowsill look somehow wrong, too functional.
The most suitable dishes are plastic.
Replanting can be done at any time, but the substrate must be dry. The remaining soil from the roots must be removed (at least the bulk).
For watering, use as soft water as possible. First watering after wintering clean water!
Added nutrients must be completely dissolved. The first watering with a nutrient solution is carried out during the period when the plants are in a state of obvious vegetation. Alternate watering with a nutrient solution with watering with clean water. Do not reuse nutrient solution and water. Remove any remaining liquid from the pan.
Ready-made fertilizers are not formulated exactly to meet the requirements of cacti (compare the chemical composition of several sold). Therefore, it is necessary to have 3-4 types and change them. At the beginning of the growing season, use more often with relatively high content nitrogen, before flowering - phosphorus, in preparation for wintering - potassium.
I believe, that:
Chemoculture is a complex growing method in which the cactus grower can make many irreparable mistakes. It requires great theoretical knowledge and experience.
Now about growing in soil mix.
The composition of the soil mixture must include two mandatory components: nutritious (leaf humus, clay turf) and loosening (fine and coarse sand, crushed stone, crushed brick).
Coarse and medium fractions of river sand are most often used as a leavening agent. A good alternative is fine granite chips, ideal for simulating mountain and rocky soils.
For physiologically safe moisture retention, crushed brick or charcoal are often used.
80% of all types of cacti will grow well in universal cactus mixture: 1 part leaf soil, 1 part turf soil, 1 part coarse river sand with the addition of broken red brick.
Epiphytic species(schlumbergera, epiphylum, rhipsalis, etc.) require an increase in the content of leaf soil, and species with a thickened (turnip) root- turf land.
In addition, almost all cactus growers practice their own “trademark” “dances with tambourines.” For example, I add in large quantities spent orchid soil(rotted pine bark), which has poorly digestible organic matter, good moisture capacity and breathability, a slightly acidic reaction and has antiseptic properties, properties ideal for cacti.
Also as a leavening agent I add cherry and plum pits, well washed and steamed in the oven. They also rot slowly (5-7 years), supplying the cactus with nutrients and, as part of a high-quality soil mixture, do not become moldy.
What is a "quality potting mix"?
The initially granular and fairly water- and air-permeable soil quickly, sometimes after just a few months, loses its permeability, and its lower layers and surface acquire a cohesive structure.
Such soil has a disgusting odor, which is an unmistakable sign of spoilage. Damage begins to spread from the lower layers, which are least ventilated and retain moisture the longest.
The reasons for spoilage are excessive watering, hardness of the water used for irrigation and overloading of the soil with organic matter. Damaged soil must be replaced with fresh soil, with the composition adjusted to eliminate the causes of spoilage.
Description of the main components of the soil
And, in conclusion, a description of the main components of the soil, because. for beginners, and the article is written mainly for them, it is not clear “what is it” and “where to get it”?
Leaf ground, or leaf humus
This is a light, loose soil, easy for plants to absorb, with a slightly acidic reaction (pH 5...6). It has a good structure, consists of lumps, they are quite moisture permeable, which is very important for the normal functioning of plants. Leaf humus dries out much faster than clay soil, since it has little moisture capacity.
Adding leaf soil to the mixture prevents unwanted stagnation of water in the pot. It is obtained from fallen leaves that lie at the bases of trees and shrubs. After lying in the winter on wet ground, the leaves rot and disintegrate. In the spring you see that most of the fallen leaves seem to disappear.
The best leaf ground under linden and maple. The top (not rotted) layer of leaves is removed with a rake, and the loose layer (about 1 cm) is scraped off from the soil. This is quality leaf land.
Sod land
harvested in meadows and pastures, preferably old, fallow, perennial, with good grass-clover grass. It cannot be harvested in low-lying areas and generally in areas with high acidity.
Sod soil is obtained by shaking off cut sods at least 8 cm thick. Sod soil is quite porous, highly moisture-absorbing, and rich in essential nutrients that last for many years.
Pine bark
in crushed form, they are added to soil mixtures as a loosening and acidifying material. In America and Canada, a number of companies produce substrates for growing cacti based on pine bark.
The bark should be taken from fallen old trees, or picked from living mature pines closer to the base of the trunk. There are large bumps of bark, so you can pick them out. It is far from the wood there and the tree does not suffer, and the bark turns out to be the one that is needed. It is necessary to pay attention to the absence of resin.
At home, the bark is boiled for about two hours or soaked for several days. In this form, it is easily crushed in a rod meat grinder with the knife and grid removed. Stored in a slightly damp state.
Sand
Coarse river sand is considered the best. Unsuitable quarry sand is fine, reddish, containing ferrous compounds and oxides of other metals, harmful to plants, as well as clay and silty particles. Fine sand should never be used, since it cements the substrate.
Brick chips
Serves as a soil moisture regulator and promotes soil porosity. When watering plants, the brick absorbs excess water and then slowly releases it to the soil as it dries.
Brick chips give an alkaline reaction, so before use they are neutralized with weak acid solutions until the emission of gases completely stops, followed by washing, including from the dust fraction (until the cloudy water disappears).
Preparing high-quality soil is not only beneficial for cacti, but also improves the health of cactus growers (I mean the tourism associated with harvesting)!
Good luck and good health to you!
Vladimir Shevlyakov.
