WO2009122013A1

WO2009122013A1 - Water for watering and spraying plants, and method for preparing the same

Info

Publication number: WO2009122013A1
Application number: PCT/FI2009/050241
Authority: WO
Inventors: Päivi HENTTU; Luis SANTOS MONTALBÁN
Original assignee: Henttu Paeivi; Santos Montalban Luis
Priority date: 2008-04-02
Filing date: 2009-04-01
Publication date: 2009-10-08
Also published as: FI20085274A0

Abstract

A method for preparing water for watering and spraying plants and the water for watering and spraying plants. In order to promote the well-being of plants, the water intended for watering and spraying them is purified to remove substances harmful to the plant, whereafter pH of the water is adjusted advantageous. Thereafter, it is possible to add to the water substances promoting the well-being of the plant. The water is particularly suitable for houseplants and for use in greenhouses and nurseries.

Description

WATER FOR WATERING AND SPRAYING PLANTS, AND METHOD FOR PREPARING THE SAME

BACKGROUND OF THE INVENTION

[0001] The invention relates to a method for preparing water for watering and spraying plants, in particular orchids and carnivorous plants.

[0002] The invention further relates to water for watering and spraying plants, in particular orchids and carnivorous plants.

[0003] The use of orchids and carnivorous plants as houseplants has increased greatly. It is peculiar to these plants that they adjust to grow in low-nutrient, passive media. In order to thrive these plants require special properties of their growing conditions and irrigation water, among other things, which properties are not easy to provide by many growers, let alone a home or an amateur grower. Corresponding properties of irrigation water would also be beneficial for many other house and greenhouse plants and in particular for nursery growing.

[0004] Typically, the home growers, in particular, use ordinary tap water for irrigating houseplants, including orchids and carnivorous plants. However, the chlorine contained in the tap water is detrimental to plants, because it is absorbed through the root system to the plant and displaces oxygen in cell respiration and photosynthesis. Due to the effect of chlorine the plant suffers from internal oxygen deficit and, because of the oxygen deficit, is exposed to microbes causing decay diseases. Because of occupational safety factors and easier dispensing, typically, tap water chlorination currently employs liquid chlorine (chloramine or sodium hypochlorite solution), which will not be removed from the water by settling or boiling, contrary to common understanding. Boiling, in turn, even deteriorates the quality of water from the view point of the plants, when pure water evaporates and the saline content in the remaining water increases respectively.

[0005] In addition to chlorine, tap water contains lime, which is not good for all varieties either, even though many now commonly available orchid varieties tolerate lime for a few months, even longer, in particular when used in connection with acidic fertilizers. In addition, in the purification process the pH of tap water is adjusted excessively high in view of the environment where many house plants thrive optimally. [0006] In order to reduce the detriments caused by tap water some amateurs and home growers irrigate plants with collected rainwater, melted snow or even lake water. However, lake water is not sufficiently clean for the purpose and the purity of rainwater and melted snow is not sufficient either, especially in populated areas. Natural surface waters contain varying amounts of pollutants from traffic, industry and agriculture: fine particles, chemicals, pesticides, insecticides and other environmental toxins. Moreover, the properties of these water types vary greatly depending on the location and time of collection. In a given location at a given moment the water may be of good quality and its pH within a useful range, whereas in another location or at another moment the pH of water may be poor and the water may contain large amounts of impurities and toxins.

[0007] The amateur growers, home growers and greenhouse and nursery growers alike share a problem that the plants die from mould and other similar infections. One important factor in creating this problem is that the irrigation water used, typically tap water, contains minerals which encourage the proliferation of mould spores, bacteria and other microbes. Professional growers, in particular, typically try to reduce infections by using pesticides, but that is not always good for the well-being of plants, and it may be particularly problematic in connection with useful plants.

[0008] It is commonly known to purify water by distillation. The purity of water obtained by distillation depends greatly, however, on the employed process and devices. The greatest problem with distillation is, however, the large amount of energy required, because heating, boiling and cooling of water are all energy-intensive operations. So, the use of distilled water is not an economically useful option for water purification when tending plants.

[0009] Typically, activated carbon filtering and reverse osmosis are used in laboratories for purifying water to remove harmful impurities, but equipment required for this are too expensive for amateur and home growers, for example. Because of the costs only few of the nursery growers use any kind of water purification, and even they use economical but less effective sand filtering; typically, nursery growers do not adjust the pH value at all, because optional methods include expensive titration and time-consuming and unreliable pH adjustment in containers, in which typically a daily or weekly demand of water is mixed at a time. Laboratories, in turn, purify and adjust their water supply to be exactly suitable for their own purposes, but in laboratories purified and adjusted water is not used, however, for watering or spraying plants, but for manufacturing in vitro growth media for plants. However, the requirements set for growth media differ considerably from those set for water intended for watering and spraying.

[0010] In a typical water purification process the pH of tap water is adjusted to the range of 6.5 to 9.5. If the water is neutral or close to neutral, the plants do not actually suffer from it, but the intake of some micro nutrients, such as iron, for instance, becomes more difficult if pH is above 6.5. And, as pH value rises towards the upper end of the variation range, tap water is harmful, even in short exposures, to delicate plants, such as orchids and carnivorous plants. Moreover, neutral or alkaline tap water causes lime formation.

[0011] From publication US 3 501 402 is known a method for preparing irrigation water for orchids from tap water. In the method, tap water is first conveyed into a closed tank or recipient, which contains ion exchange resin for removing sodium from the water. From this recipient the water is further conveyed along a pipe into a second closed tank or recipient, which contains calcium-containing mixture, such as lime stone, for raising the pH value of the water and for adding lime to the water. However, the method does not provide sufficiently good irrigation water, and according to current understanding, a high pH value is not good for orchids, and also lime is harmful to at least some varieties.

BRIEF DESCRIPTION OF THE INVENTION

[0012] The object of the present invention is to provide novel and improved water for watering and spraying plants, in particular orchids and carnivorous plants.

[0013] The method of the invention is characterized by purifying water to remove substances that are unbeneficial to a plant or plant group such that conductivity of water is less than 0.5 mS/cm, that the TDS (Total Dissolved Solids) value of water is less than 240 mg/l and the chlorine content in water is less than 20 mg/l and that the pH of water is adjusted to a range of 3.3 to 6.5 which is beneficial to a plant or plant group.

[0014] The water for watering and spraying plants, in particular orchids and carnivorous plants, in accordance with the invention is characterized in that the chlorine content in the water is less than 20 mg/l, the TDS value is less than 240 mg/l and the pH value is in the range of 3.3 to 6.5. [0015] The basic idea of the invention is that the water for watering and spraying is prepared by purifying tap water, natural water or a combination thereof, to remove substances that are harmful to the well-being of the plants, whereafter its pH is adjusted to be beneficial to the plants to be irrigated. In addition, its other properties may also be adjusted to be as advantageous as possible to the use and substances promoting the well-being of plants, such as nutrient salts, may be added thereto.

[0016] The invention has an advantage that the purified, pH- adjusted water, wherefrom are removed substances harmful to the plants to be tended, promotes the well-being of the plants and does not maintain adverse mould growth and other harmful microbe growth, such as non-purified waters containing organic solids and minerals. In addition, pH-adjusted irrigation water promotes the well-being of a plurality of plants, because most commercially available orchid varieties, for instance, have a preference for acidity and the acidity of irrigation water enhances their nutrient intake. Water for watering and spraying is particularly advantageous for various orchid varieties and carnivorous plants, for instance, but it is also advantageous for nursery growing and for almost all houseplants and greenhouse plants, except for lime-loving plants. By purifying the water first to remove substances that are harmful to the plant and by adjusting it to be beneficial to the plant and, only thereafter, by adding thereto substances that are beneficial to the plant it is possible to make sure that the beneficial substances have been added to the pure water un- harmful to the plant. In that case it is also possible to make sure that the values of the prepared irrigation and spraying water consist of minerals and the like that are useful and not harmful to the plant.

DETAILED DESCRIPTION OF THE INVENTION

[0017] In the method of the invention the irrigation and spraying water is purified utilizing reverse osmosis, activated carbon filtration, ion exchanger and/or some other similar purification method to remove lime, chlorine and other components harmful to plants, such as chlorine, lime, mineral salts, fine particles, pesticides, insecticides and other environmental pollutants, such that the chorine content, and advantageously also salinity in the water, can be arranged to a level that is beneficial to the plants. For the well-being of the plants, an advantageous salinity value of the irrigation and spraying water is less than 50 mg/l, whereby the conductivity of water prior to adding optional nutrient salts is less than 0.5 mS/cm. More preferably the salinity value is less than 20 mg/l and the conductivity of water is 0.2 mS/cm and most preferably the salinity value is less than 5 mg/l and the conductivity of water is respectively less than 0.05 mS/cm. The preferable salinity values may be determined on the basis of the conductivity of water, because the ions of salts dissolved in the water conduct electricity and thus raise the electrical conductivity of water. After purification the chlorine content in the water is less than 20 mg/l, more preferably less than 5 mg/l and most preferably less than 1 mg/l. Further, the water is purified such that the TDS (Total Dissolved Solids) value of the water is less than 240 mg/l after purification, more preferably less than 100 mg/l and most preferably less than 50 mg/l. In different embodiments the water may be further purified such that its bacterial content is less than 100 cfu/ml, more preferably less than 50 cfu/ml and most preferably less than 10 cfu/ml.

[0018] After the water is purified to remove substances harmful to plants, its pH is adjusted, in the solution of the invention with an acid, for instance, to be as beneficial as possible to the plants, for orchids preferably to pH 3.3 to 6.5, more preferably 4.4 to 6.0 and particularly preferably to pH 5.7. The acid used is preferably a strong acid that is beneficial to the well-being of the plant, such as nitric acid or phosphoric acid that are widely used in the manufacture of fertilizers, for instance. Whereas weak acids are not so suitable for this purpose, because protolysis of weak acids is incomplete, and consequently there may be residual active ion groups in the water which may react with nutrient salts, if any, and form undesirable reaction products, or they react with the surface structure of the plant and cause so-called burn damages or spottiness.

[0019] The irrigation and spraying water prepared with the above- described method and having no added nutrients is intended for watering and spraying houseplants, advantageously orchids and carnivorous plants, in order to maintain a sufficient moisture balance, but it may also be used for other purposes and for other plants. The water is purified and its pH is adjusted as described above, whereafter the water does not contain adverse amounts of un- beneficial substances for the purpose and the water does not have any other disadvantageous properties from the viewpoint of the plants. In various embodiments it is also possible to add to the water various chemicals and other substances beneficial to the plant, by means of which substances it is possible to inhibit proliferation of moulds and bacteria, for instance. The water is particu- larly intended for watering and spraying, but some embodiments thereof may also be used for certain fertilizing purposes, in particular to act as a root or leaf fertilizer. In that case to the purified water there are added useful nutrient salts for the plant growth, such as ammonium nitrate or iron chelate, particularly Fe- EDTA. After this addition, the conductivity and pH of the water are within a range that is advantageous to a plant or plant group, typically 0.2 to 2 mS/cm and 3.3 to 6.5 It is essential to note that the conductivity higher than in the purified water used as a base is now expressly caused by minerals that are beneficial and not unbeneficial to the growth of plants. Various embodiments of the irrigation and spraying water suitable for use as fertilizers are described in greater detail hereafter. The ready-made irrigation and spraying water may also be packaged in consumer packages which are suitable for home and amateur growers and in which it may be distributed for retail sale. Apart from an ordinary bottle, these consumer packages may be pump bottles or spray bottles, the purpose of which is to make the use of the products easier.

[0020] Further, the water may be pasteurized, i.e. heat treated, one or more times prior to packaging and/or thereafter. A heat treatment of this kind may destroy the pathogens and contaminating micro-organisms that may have passed through the preparation process. If the heat treatment is repeated in sequences of two or more successive heatings, retentions and coolings, the retention time may be shorter than in a treatment comprising one heating- retention-cooling cycle.

[0021] In the heat treatment the water with or without fertilizer is heated preferably to a temperature of 63 ⁰C to 138 ⁰C, more preferably to 70 ⁰C to 120 ⁰C and most preferably to 80 ⁰C to 100 ⁰C. The retention time at the target temperature is preferably 1 to 60 seconds, more preferably 10 to 30 seconds and most preferably 15 to 20 seconds.

[0022] After a typical water purification process the pH of tap water or natural water is generally 6.5 to 9.5, which at the lower end of the variation range already starts hampering the intake of micronutrients, such as iron, of the plants and at the upper end of the variation range will be harmful, even in brief exposures, particularly to delicate plants, such as orchids and carnivorous plants. Thus, it is essential to the well-being of the plants that the properties of the irrigation and spraying water are adjusted after the purification. Moreover, a neutral or alkaline pH of the water increases lime formation. [0023] In addition to the salinity, pH value and TDS value of the irrigation and spraying water, it is also possible to adjust the bacterial content of the water. Moreover, it is possible to add to the water various substances that are beneficial to the plant, plant group or a growth phase thereof, such as oxygen, plant hormones, such as gibberellins, antimicrobial agents preventing growth of microbes, such as bacteria, algae and moulds, fertilizers, plant extracts or combinations thereof. For instance, carnivorous plants secrete in their cells substances that inhibit growth of bacteria and moulds. These substances may be isolated from the carnivorous plants and added to waters for watering other plants, whereby the resistance of the plants to be watered may be improved against bacteria and moulds.

[0024] The basic idea of an embodiment is that the pH-adjusted water, from which substances harmful to the plants to be tended have been removed, is fertilizer-free and it is used, for instance, during dormancy for watering and spraying plants. In that case oxygen may be advantageously added to the irrigation and spraying water.

[0025] The basic idea of an embodiment is that the pH-adjusted water, from which substances harmful to the plants to be tended have been removed, is optimized for leaf fertilization. It is particularly advantageous to use the leaf fertilizing water for spraying the plant or plants during active growth prior to flowering and during flowering, like in the spring. For this purpose, gibberellins, nitrogen, oxygen or combinations thereof are advantageously added to the purified water, before or after pH adjustment.

[0026] Fertilizers intended for pot plants, in particular orchid fertilizers, do not typically contain calcium or magnesium, because it is assumed that they are found in sufficient amounts in the substrate, such as soil, or in the non-purified irrigation water. However, the calcium and magnesium present both in the tap water and in the natural waters have reacted with one another and with oxygen, and therefore they are not in a usable form for plants. Hence, it is not advisable to include simultaneously both calcium and magnesium in the fertilizer solution, due to their mutual reactivity, but since both calcium and magnesium are necessary substances for plant photosynthesis, they may be provided as a leaf fertilizer. In the spraying water it is possible to add calcium nitrate (Ca(NO₃)₂), preferably 5 to 20 g/l, more preferably 5 to 15 g/l, particularly preferably 10 g/l (fertilizer 1 ), or magnesium sulphate (MgSO₄) preferably 5 to 20 g/l, more preferably 5 to 15 g/l, particularly preferably 10 g/l (fertilizer 2). In that case, fertilizers 1 and 2 may be delivered alternately as a leaf fertilizer, for instance alternating in two-week periods. These leaf fertilizers should be delivered throughout the whole growing period.

[0027] Further, according to an embodiment, in addition to the fact that water is purified to remove substances harmful to the plants and pH is adjusted to be advantageous, the water is optimized for root fertilization. It is particularly advantageous to use root fertilizing water for watering plants after flowering. For this purpose, gibberellins, nitrogen, oxygen, calcium, magnesium or combinations thereof are preferably added to the purified water before or after pH adjustment.

[0028] The principal nutrients of plants include nitrogen, phosphorus and potassium. Thus, the fertilizer types are often determined on the basis of their nitrogen-phosphorus-potassium ratio (hereinafter N:P:K ratio). A preferable N:P:K ratio for orchids varies not only according to growth phase but also according to species. Generally, orchid fertilizers should be mild and the conductivity of their delivery mixture should not exceed 400 μS/cm. For Cattleya and Cymbidium orchids a preferable N:P:K ratio is 1.0:0.4:0.8. Phalaenopsis and Paphiopedilum orchids require of their fertilizer an N:P:K ratio of 1.0:0.8:1.3. The Dendrobiums, in turn, require a ratio of 1.5:1.5:1.0. In the flowering period a preferable N:P:K ratio for Dendrobium and Oncidium orchids is from 1.2-4.6:1.1-4.3:1.2-2.8, particularly preferably 2.3:2.2:1.4. In the vegetative growth period a preferable N:P:K ratio for Arachnis and Aranda orchids is 0.6-2.5:0.5 -2.2:0.5-1.8, particularly preferably 1.3:1.1 :0.9.

[0029] According to an embodiment of the invention the pH adjusted water, from which substances harmful to the plants to be tended are removed, may also be optimized for treating unhealthy plants, for instance, as the roots of the plants have decayed, which is a common problem in particular in home growing. For this purpose agents inhibiting growth of microbes in particular, such as bacteria, algae and moulds, are added to the water; typically, different types of microbes have specific inhibiting agents. Additionally, it is possible to add to the water preferably plant extracts and particularly preferably oxygen. This is due to the fact that bacteria causing root decay are often anaerobic bacteria, whereby irrigation water, to which oxygen is added, is efficient in control and prevention of root decay. For this purpose it is possible to add to the purified and pH-adjusted water hydrogen peroxide (H₂O₂), preferably 10 to 1000 ml/I, more preferably 300 to 700 mg/l, particularly preferably 500 mg/l. In that case the pH adjustment of the water may be carried out with phosphorus acid, for instance, which stabilizes the hydrogen peroxide in the aqueous solution.

[0030] According to yet another embodiment the irrigation and spraying water may be optimized to increase the flower size and/or to prevent unopened flower buds from wilting and falling. In that case it is possible to add gibberillins in the irrigation and spraying water, preferably 5 to 1000 ppm, more preferably 30 to 400 ppm, particularly preferably 50 ppm, whereby it is possible to increase the length of the raceme and the diameter of flowers particularly of Cymbidium and Dendrobium orchids and to prevent premature falling of flower buds and thereby to increase also the number of flowers in the flower stem as well as to make flowering earlier. Particularly preferably the irrigation and spraying water of this embodiment may be delivered as a leaf fertilizer.

[0031] For orchids and carnivorous plants of various types or for other similar plants it is possible to optimize specific irrigation and spraying waters. Thus, it is possible to adjust the best possible pH value, salinity and chlorine content for each particular species. In addition, it is possible to ensure the most preferable TDS value and bacterial content for each particular species. In addition to this, if so desired, it is possible to add to the irrigation and spraying water the most preferable combination of oxygen, growth hormones, antimicrobial agents, fertilizers and/or plant extracts for each particular species.

[0032] In some cases features presented in this application may be used as such, irrespective of other features. On the other hand, features presented in this application may be combined, when necessary, to provide various combinations.

[0033] The specification of the invention is only intended to illustrate the inventive idea. The details of the invention may vary within the scope of the claims.

Claims

1.- Water for watering and spraying plants, in particular orchids and carnivorous plants, characterized in that chlorine content in purified water is less than 20 mg/l, TDS (Total Dissolved Solids) value is less than 240 mg/l and pH value is 3.3 to 6.5.

2. The water for watering and spraying plants according to claim 1, characterized in that bacterial content of the water is less than 100 cfu/ml.

3. The water for watering and spraying plants according to claim 1 or 2, characterized in that conductivity of the purified water is less than 0.5 mS/cm.

4. The water for watering and spraying plants according to any one of claims 1 to 3, characterized in that the purified and pH-adjusted water contains antimicrobial agents or combinations thereof for preventing the growth of bacteria, algae, moulds and other microbes.

5. The water for watering and spraying plants according to any one of the preceding claims, characterized in that the purified and pH- adjusted water contains oxygen.

6. The water for watering and spraying plants according to any one of the preceding claims, characterized in that the water contains growth hormones, such as gibberellins.

7. The water for watering and spraying plants according to any one of the preceding claims, characterized in that the water contains nutrients.

8. The water for watering and spraying plants according to claim 7, characterized in that the water contains calcium nitrate (Ca(NO₃)₂) or magnesium sulphate (MgSO₄).

9. The water for watering and spraying plants according to claim 7 or 8, characterized in that the water contains nitrogen, phosphorus and potassium.

10. The water for watering and spraying plants according to any one of the preceding claims, characterized in that plant extracts have been added to the water.

11. A method for preparing water for watering and spraying plants, in particular orchids and carnivorous plants, characterized by purifying the water to remove substances unbeneficial to a plant or plant group such that conductivity of the water is less than 0.5 mS/cm, that TDS (Total Dissolved Solids) value is less than 240 mg/l and chlorine content of the water is less than 20 mg/l and that pH value of the water is adjusted to pH value of 3.3 to 6.5 beneficial to a plant or plant group.

12. The method of claim 11, characterized by adjusting the pH value of the water with an acid.

13. The method of claim 12, characterized in that the acid used for adjusting the pH value of the water is a strong acid.

14. The method of any one of claims 11 to 13, characterized by purifying the water such that its bacterial content is less than 100 cfu/ml.

15. The method of any one of claims 11 to 14, characterized by adding to the water antimicrobial agents or combinations thereof to prevent the growth of bacteria, algae, moulds and/or other microbes.

16. The method of any one of claims 11 to 15, characterized by adding oxygen to the water.

17. The method of any one of claims 11 to 16, characterized by adding growth hormones, such as gibberellins, to the water.

18. The method of any one of claims 11 to 17, characterized by adding nutrients, such as calcium nitrate, magnesium sulphate, nitrogen, phosphorus and/or potassium, to the water.

19. The method of any one of claims 11 to 18, characterized by adding plant extracts to the purified water.