Hydrangeas are flowering shrubs commonly found in gardens and parks. Some varieties are grown as houseplants. Hydrangeas love elevated soil acidity. For this reason, there are several methods of soil acidification.
What soil hydrangea needs
The most favorable for hydrangeas is clayey acidic soil. It is this composition that guarantees lush flowering and rich color of the petals. Worst of all plants feel in sandy or alkaline soil. Neutral soil allows you to grow hydrangeas, the inflorescences of which are light in color.
Hydrangeas - Flowering Shrubs
Depending on the level of acidity, the color of the petals can vary from dark purple to pale pink. Experienced gardeners are able to achieve certain shades using various additives when watering. For example, manganese is used to produce pink flowers. An alternative solution is citric acid for hydrangea, the proportions are determined by the desired color. Lemon and vinegar are used to produce dark shades of blue. The dependence of the color of flowers on acidity indicators is shown in the table.
| pH | Color inflorescences |
| 4 | Purple |
| 4,5 | Blue |
| 5,5 | Blue |
| 6,5 | Dark pink |
| 7 | Light pink |
It's important to know! To maintain the necessary color, maintain an appropriate level of soil acidity.
How to acidify hydrangea soil
To acidify the soil using additives that are dissolved in water for irrigation. Depending on how much it is necessary to increase the pH level, substances with varying degrees of acidification are used. It is worth considering in more detail how to acidify the soil for hydrangea.
The color of the flower depends on the pH level
Using popular tools
Each method deserves special attention:
- Lemon acid. To obtain a solution, you need to mix 12 liters of water with 1 tsp. citric acid. Watering is carried out once 25-30 days to maintain an optimal level of acidity. As an alternative, lemon juice is used.
- Table vinegar. Use 9% essence, which is diluted in water in a proportion of 200 g per 20 liters. The method allows you to acidify the soil, but the effect is short-lived. It is noted that the use of vinegar negatively affects the microflora of the soil.
- Succinic acid. The use of this drug not only increases the acidity of the soil, but also serves as top dressing for the plant. The solution is prepared at the rate of: 3 tablets per 1 liter of water. If the drug is bought in a different form, then it is worthwhile to adhere to the proportions on the package in order to feed the flower, and not harm it.
- Apple vinegar. The solution is prepared from a bucket of water and 1 tablespoon of vinegar. Acidify the soil no more than 1 time in 3-4 months. It significantly increases acidity and is less harmful than table vinegar. This acidifier has a negative effect on the soil.
- Oxalic acid. Every 1-2 months, watering is carried out with water containing oxalic acid, which is added in a ratio of 100 g per 10 liters. It is advisable to first dilute the required number of crystals in a glass of warm liquid, and then add this solution to a bucket of water.
Popular soil acidification products
Most gardeners prefer succinic and oxalic acid. Citric acid for hydrangea is often used. Vinegar is less commonly used due to its negative effect on the state of soil microflora. How to water hydrangea with vinegar and whether it can be done - each grower decides for himself.
Note! It is important to strictly observe the proportions of the preparation of solutions. Their non-observance can lead to deterioration of the state of plants.
The use of mineral oxidizing agents
Preparations such as colloidal sulfur and sulfates are used to oxidize heavy clay soil. They have a strong and lasting effect. Application Features:
- Colloidal sulfur. The drug is applied in a dry form under each bush at the rate of 30 g per 1 m². The surface of the soil is loosened and buried powder by 15 cm. The method is used in the fall, so that its activation began in the spring under the influence of melt water. It is enough to add sulfur every 2 years.
- Sulphates. Apply iron sulfate in an amount of 50 g per 1 m² plot. Make dry in the fall directly into the ground. Sometimes ammonium sulfate is used (at your own peril and risk).
- Ammonium nitrate and potassium sulfate. Drugs are relevant only when the deviation from the norm is insignificant. A solution of nitrate is prepared at the rate of 30 g of the drug per 10 l of water. Make under each bush in the spring or in the fall.
Helpful information! Mineral oxidizing agents are best used as rarely as possible. Frequent application of such drugs can harm plants.
Organic Acidifiers
There are several methods to make the soil acidic for hydrangea. They include the introduction of natural components into the soil or mulching the surface around the plants.
Natural remedies are environmentally friendly and safe.
Actual tips:
- Deciduous humus. It is preferable to use rotten oak leaves. The introduction of compost into the soil increases acidity and also enhances its nutritional value.
- Needles of larch. For mulching plantings, needles of coniferous trees are used.
- Horse peat. It is used as mulch or added to the soil for planting hydrangeas. Acidity increases significantly, but the process will take some time.
Methods that involve the use of organic matter to acidify the soil are environmentally friendly and beneficial. The only drawback is the delayed action. For this reason, humus or peat is added to the site in advance.
Additional Information! Use peat should only be used to acidify the soil. As mulch or fertilizer, only low-lying peat is suitable for flowers.
Soil oxidation technology
It is important to follow a strict sequence of actions aimed at increasing the acidity of the soil. Initially determine the pH level, which is carried out by using a litmus test. It is purchased in any garden center and measured according to the instructions attached to the product. There are several rules:
- for a slight increase in acidity, a solution of citric acid or ammonium nitrate is used;
- vinegar and citric acid will help to quickly increase indicators;
- it is safe to acidify the soil by adding peat or compost from oak leaves to the soil.
Some substances are dissolved in water, and some drugs are embedded in the ground in autumn in dry form. It is necessary to strictly observe the proportions, watering the hydrangea with citric acid and other solutions is carried out only under the root. The key to success is adherence to technology. Otherwise, home flowers will be damaged.
Failure to comply with proportions leads to plant diseases
How to maintain the resulting acid-base balance
As panicled hydrangea grows, the acidity of the soil in the plot changes. Indicators may deviate from the norm. To maintain the pH at a given level, apply irrigation with solutions of citric, succinic and oxalic acid. The drugs are able to maintain an acid-base balance favorable for hydrangeas.
Mulching with peat and needles throughout the entire period of growth and flowering increases acidity. The mulch layer is updated annually, replacing the substrate completely or thickening its layer. This rule also applies to compost from oak leaves, which is used to mulch plantings.
The mulch layer needs to be updated
Means for increasing the amount of alkali
Sometimes there is a need to return the level of acidity to baseline. This is usually due to the fact that at the site of hydrangea growth, other plants are preferred to prefer a more alkaline environment. In this case, there is a need for deoxidation of the soil. Most often, lime is used for this purpose.
Liming the soil involves a series of actions:
- Ground limestone is poured into a barrel, pot or other container and poured with water. 1 part of limestone requires 10 liters of water.
- The soil is watered with lime infusion. After 2-3 days, they begin to sow or plant plants.
Instead of lime, you can use chalk. The main condition is that it is introduced in the spring before harrowing. Use crushed dry chalk, which is used at the rate of 100-200 g per 1 m². The amount of substance depends on the degree of soil acidity and indicators to which it must be reduced.
Dolomite flour may be used as an alternative to lime, but this is not safe. For some cultures, this deoxidation is harmful.
Note! Dolomite flour should not be added to the area intended for gooseberries, sorrel, blueberries and cranberries.
Hydrangeas have special soil requirements. Alkaline soil does not suit them - they prefer acidic and slightly acidic soils. In most cases, it is necessary to artificially increase the level of acidity, as well as maintain it throughout the life of plants. You can use different methods, but how to acidify hydrangea, each grower decides for himself.
