When do we start fertilizing blueberry?

 Blueberry is a shrub that requires specific growing conditions, and a well-planned fertilization schedule from the breeder. What conditions do blueberries need to develop properly and bear fruit abundantly? When do we start fertilizing blueberry? Learn the basic principles of feeding the bush.

We often hear the opinion that the blueberry is a difficult shrub to cultivate, and the effects, i.e. the fruit, do not meet the expectations of the grower in terms of taste and quality. So let's dispel this myth. Blueberries really have quite specific requirements, but sticking to a few basic rules will allow you to enjoy a tasty crop, and the bush itself will develop properly.

blueberry on a green branch

Blueberry cultivation rules

The efficiency of cultivation is mainly influenced by the type of substrate, position and proper feeding. We wrote about the basics of blueberry cultivation in this article.

SUBSTRATE FOR CULTIVATION OF BLUEBERRY

The success of cultivation depends mainly on the type of substrate. Blueberry is restrictive in this respect, which is caused by the structure of the underground part, i.e. the roots. The root system of the shrub is strongly developed, but shallow, which translates into a lower ability to absorb nutrients from the deeper layers of the substrate.

The above factor means that the blueberry must be planted in a substrate with specific parameters and should be regularly fed with nutrients adapted to specific needs and development phase.

Blueberry should be planted in a permeable, moderately moist, humus and acidic substrate. The optimal pH of the substrate should be in the range of 3.0 to max. 5.0. If the soil in the garden does not meet these conditions, it is necessary to improve its physical properties by mixing with acidic peat and coarse sand. Peat will increase the acidity of the substrate, lowering the pH to the appropriate level, and in combination with sand, it will additionally loosen it, which will minimize the risk of long-term water stagnation.

POSITION FOR AMERICAN BLUEBERRY

The position for the cultivation of blueberries should be well sunny, warm and sheltered from strong gusts of wind. The shrub does not tolerate shade well, which results in inhibition of development and a significant reduction in yields.

Blueberry fertilization

Meeting the above requirements of the plant is a milestone in achieving satisfactory cultivation results. Proper acidity of the substrate translates to the greatest extent into the plant's ability to absorb nutrients, but in the case of American blueberry, it is necessary to systematically feed it through fertilization

When and what to fertilize blueberry?

The timing of blueberry fertilization and the type of fertilizer are crucial.

Spring fertilization is based mainly on preparations rich in nitrogen, which causes faster growth of the plant. It is recommended to start supplying the bushes with nitrogen right after they bloom. The next two doses should be delivered to the plants in June - the first at the beginning of the month, the second at the end or beginning of July, after the end of the phase of the strongest fruit growth.

Among the nitrogen preparations that will work well for fertilizing blueberries, we can mention, among others, ammonium sulphate and ammonium nitrate. The recommended dose is 30-50 kg per hectare.

Autumn fertilization should be carried out in early autumn, at the turn of September and October. Contrary to the spring feeding, nitrogen should be avoided after the growing season and replaced with agents whose main elements are potassium and phosphorus, which will strengthen the plant before the winter period and protect against less favorable weather conditions.

 

Potassium preparations are, for example, potassium sulfate and potassium salt, while phosphorus preparations include ammonium phosphate. The doses for these are 50-75 kg per hectare (potassium) and 30-60 kg per hectare (phosphorus).

In addition to the preparations listed above, you can also use ready-made products available in gardening stores. This solution will help especially novice growers, but not only, because ready-made mixtures are perfectly balanced, therefore they perfectly meet the specific needs of blueberries.

Among the multi-ingredient fertilizers intended for the cultivation of blueberries, there are Substral American blueberries, Florovit blueberry and acidophilic fertilizer and Target blueberry fertilizer.

Ready compound fertilizers contain optimal amounts of micro- and macroelements, and also acidify the substrate, thus creating conditions adapted to the needs of the plant.

How to fertilize American blueberry?

Bilberry prefers soil fertilization, and the preparation should be sprinkled directly under the bush, within the root zone.

Foliar fertilization is less recommended, but also used, especially in the case of a deficiency of a specific element.

Avoid organic fertilizers in the form of manure or compost, which are characterized by a high, alkaline pH, which the plant does not tolerate.

Fertilization should be carried out on a rainless day to avoid the fertilizer granules sticking to the leaves.

After fertilization, the bushes should be watered.

It is necessary to comply with the doses recommended by the manufacturer. Instructions for a specific preparation can be found on the packaging.

In the case of blueberries, it is also necessary to mulch, which protects against excessive weed infestation, but also provides the plants with the appropriate pH of the substrate, moisture and humus. Pine bark, sawdust or needles can be used for mulching.

Diagnosing nutrient deficiencies

One method is to observe the plants.

too little nitrogen will cause growth inhibition, yellowing and then reddening of leaves and shoots

over-fertilization with nitrogen will translate into excessive growth of the plant and green discoloration of the leaves even in autumn

potassium deficiency results in browning and curling of the leaves inwards

an excess of potassium can be noticed after leaf fall caused by the appearance of chlorosis on their edges, i.e. a disease disorder involving disturbances in the production of chlorophyll

too little phosphorus in the substrate will translate into purple coloring of petioles and leaf blades

if the pH is too high, the blueberry will stop growing and its leaves will turn yellow and start to fall off.

It is recommended that before starting the cultivation of blueberries, a detailed chemical analysis of the soil should be carried out, which will help determine the optimal doses of individual elements. For greater effectiveness, laboratory tests should be repeated in subsequent seasons.