How-To

Strawberry Leaves Turning Red – Why Is This Happening?

The term ‘strawberry’ describes a plant that bears fruits in the shape of a small, rounded, green-topped berry-like fruit. It is one of the most popular cultivated fruits in total production worldwide. Strawberry plants are classified into two types: flowering and non-flowering. The non-flowering type produces berries all year round, whereas the flowering type only flowers when conditions are right. The flowers produce fruit during the spring and summer but not much because they need high temperatures. Only during winter do these plants flower-producing fruit. If you see your plants turning yellow or red on their leaves, you should have them tested by a qualified person who can determine whether the cause is due to an infection or if it’s just a leaf color change.

What causes strawberry leaves to turn red?

Many factors may lead to this phenomenon, including;

  • Too much acidity or alkalinity from the soil or water: An excess amount of acidity will reduce photosynthesis leading to reduced growth and poor quality of fruit. Alkaline soils are more susceptible than acidic ones. Soil pH can be maintained between 5.2 and 7.0, giving optimal growth and health. A pH below 5.5 or above 7.8 is likely to result in disease problems. Excess lime also leads to excessive salt levels in the soil, which reduces yield and overall quality. This means less fruit or seed and lower sugar content. Water should be amended using slow-release fertilizers such as those made by Planting. These fertilizer applications should include Nitrogen, Phosphorus, Potassium, Calcium, and Magnesium.

  • Fungi: Many fungal diseases attack strawberries. Some of these fungi thrive at a warm temperatures while others thrive at cool temperatures. A few examples are Botrytis cinerea – commonly known as grey mold- and Septoria lycopersici – downy mildew. These fungi affect foliage and fruit, reducing yields and causing premature ripening. They can generally be treated successfully with fungicides. If the problem persists, consider cutting off affected foliage and destroying it before it spreads to other parts of the crop. Always wear protective clothing when handling infected material. You should also avoid spraying any areas with an outbreak of either fungal disease.

  • Poor fertility from lack of fertilizer: Strawberries need constant feeding throughout the season. Plants grown without adequate nutrition often produce stunted fruit and low sugar levels. 4. Lack of potassium: Potassium is essential to growing healthy strawberries. A deficiency of potassium can lead to early fruiting and smaller fruit size. Other symptoms include pale, yellowish leaves, irregular growth, weak stems, and poor root development. A low level of potassium is usually caused by a combination of inadequate rainfall and fertilizer application.

  • Too little phosphorus: P is required to produce chlorophyll, an important component of photosynthesis. Without sufficient amounts of phosphorus, the plant cannot use light energy through photosynthesis, resulting in decreased growth rates and a reduction in the size and weight of the fruit. P must be applied several times during the growing season to ensure optimum uptake and concentration in young tissues and roots.

  • Low magnesium: Mg acts as an activator of enzymes involved in cell division and nutrient transport. It helps regulate enzyme activity, increases resistance to drought stress, and improves tolerance to chilling injury. It also regulates the stomatal aperture and promotes flowering. The optimum form is MgH20 (magnesium hydroxide), but you can choose from the various forms depending on your needs.

  • Drought stress: When moisture levels fall below minimum requirements, the plant may become stressed and wilt, losing electrolytes and water. As the plant loses water, the surface dries out and gets hotter resulting in rapid wilting. In very hot conditions, the moisture content quickly drops below 50%, so that plants may die. High winds cause further stress and may damage the leaves.

  • Cold temperatures: Like most plants, strawberries stop growing rapidly around 0°F. This means they lose their ability to make new cells. So even if the air temperature remains at 5°F above freezing, under-fertilized crops will not grow properly. However, high humidity encourages more rapid growth than cold air. Therefore, when choosing a site, remember that some strawberry varieties require higher soil temperatures than others.

  • Insects: These vary from general insect pests such as leaf hoppers or grasshoppers to specific harmful insects like the raspberry fruit borers that feed on the flowers. Keep the beds well weeded and mulched, and regularly check for worms and slugs. Do not let them settle near the plants because they will eat all the foliage.

  • Over watering: Most fruits are heavy growers, and they do require plenty of water. But too much water causes the fruit to become soft with reduced firmness and flavor. Even though the plant absorbs the water, it will find its way to the lower leaves and eventually into the fruit, so it’s always better to apply less rather than get carried away. Water evenly until fruit matures; only after this point can you reduce doses slightly. If the weather has been particularly dry over summer, it might be necessary to top-dress the plants with extra liquid.

  • Too much carbon: A certain amount of CO2 is needed to produce fruit – about 200 ppm. However, too much can also kill a plant and cause the fruit to ripen prematurely and rot before picking. You should get just the right balance between these two things. For example, a planting medium containing 400ppm CO2 would need to add 40kg per sq m. This would allow 15 kg of fresh air into each square meter of bed every 24 hours! To avoid excess carbon dioxide being released into the atmosphere, you should only add enough CO2-rich material to offset what is lost each day from the crop.

Solutions for strawberry leaves turning red.

The following are the possible solutions for strawberry leaves turning red:

  • Use fertilizers recommended for organic gardening: The best type of fertilizer to use is one made from natural sources which does not contain any artificial ingredients. Apply it through the drip system supplied with your irrigation supply (if using an open sprinkler system). Choose a balanced formula containing protein, potassium, phosphorus, and calcium. Avoid applying fertilizer to wet leaves; wait until they have dried out. It is also important to avoid spreading manure or compost on the leaves, as this could promote disease problems.

  • Avoid adding extra nutrients during late spring through to early autumn, which can lead to excess nitrates in the fruit: Nitrogen is present in both soils and fertilizers and is essential for healthy plant growth. There is no harm in adding nitrogen to your garden, but the excessive application may lead to premature flower drop in the fruit production stage, causing a reduction in quality. This effect can last up to 6 weeks, depending on how often you fertilize.

  • Planting in rich soils: Rich soils have high levels of humus (a compound that helps retain moisture) and lots of good minerals. They hold a lot of nutrients for the roots to absorb and help the plants improve their health. Plants grown in nutrient-poor soils tend to look dull due to poor nutrition. Plants can’t store vitamins and minerals efficiently in their tissues unless there is sufficient soil available for them to take up. So if you want to grow big, succulent strawberries, try growing them where conditions are ideal.

  • Maintain pH: Acidic and alkaline soils cannot support all types of plants and will result in stunted growth. The key is maintaining a correct level of acidity or alkalinity throughout the season. Keep the soil pH at around 5.5-6.0 and never let it drop below 4.8. Remember that the pH test kit needs to remain stable when testing soil samples – don’t change the container or touch the sample once it is taken out of the packaging.

  • Fertilize in autumn: It’s better to give your plants some concentrated food after flowering rather than watering them in summer. Because the fruits are set to ripen, you must protect them against pests by spraying insecticides. Be careful if you use any weed killer, such as glyphosate, because it can affect your strawberries’ taste, color, and size.

  • Don’t water excessively in hot weather: Watering your plants too frequently causes leaf burn and reduces their ability to take up water and nutrients. You can expect to lose 1/3 of your plants’ weight each week. Watering isn’t necessary until temperatures reach 10 degrees above normal. Try to control the shower volume so that no more than half of the leaves get watered at one time.

  • Prune regularly: Regular pruning promotes stronger stems and healthier growth. Strawberries benefit from pruning between May and August. Remove dead flowers and old wood, though only cut back about two-thirds of the length of the shoot. You should always leave just enough feeder branches remaining on fruiting canes to continue feeding the developing fruit.

  • Improve air circulation within the greenhouse/strawberry patch: Air circulation is vital to keeping your plants moist, reducing stress, and encouraging fresh fruit sets. This means ensuring the walls are kept damp, and the windows shut tight. During the winter, it is advisable to close them off completely to prevent drafts from entering from outside.

  • Choose disease-resistant varieties: With over 100 diseases known to attack strawberries, choosing resistant varieties is often the best defense against infection. Look for a variety with a long history of resistance to viruses, bacteria, and fungi. Avoid purchasing seedlings from nurseries as they may have been infected with unknown pathogens. Also, avoid buying small ones because they’re likely to succumb to disease quickly.

  • Mulch around stems: A light layer of mulch keeps the soil warm and protects the undersides of shoots. Mulching also prevents weeds from germinating beneath the surface and makes harvesting easier when the plants are ready to pick. Keep mulched areas well maintained as they dry out quickly. They should receive three times the amount of care as bare soil.

  • Start your gardening with certified plants only: Only buy certified plants from reputable nurseries. Always choose a nursery where staff members wear protective clothing during delivery and handling of plants. Never accept plants from an unlicensed source without asking plenty of questions first. Nursery owners are usually keen to ensure that their stock is safe but check with them before accepting delivery of new plants.

  • Plant them in areas that receive good quality sunlight for maximum hours: Light-loving plants grow much faster under full sun, so plant your strawberries early enough in spring or late enough in autumn to allow a good growing season. Plants don’t like shade; they thrive in bright conditions. The ideal situation is full sun and cool nights. For this reason, planting your berries among trees will help keep them cool if you live near forested land. Strawberries require lots of room to sprawl – ideally, a minimum area of 2m x 2m (roughly six feet by six feet).

How to Fertilize Strawberry Plants in Containers

Soil fertility can be very important to growing healthy strawberries. Many organic strawberry growers use compost tea as part of their fertilizer program. Compost tea contains beneficial microorganisms and nutrients such as nitrogen, phosphorus, and potassium.

Adding fertilizer in liquid form to the container water results in greater absorption rates than adding large amounts to the potting mixture itself. Commercial fertilizers may be used in place of compost tea, provided they contain all three major elements.

The most commonly applied commercial fertigation systems deliver nutrient packages through slow-release controlled release granules held together by polymer binders. These products can provide concentrated doses of specific nutrients.

Strawberry leaves turning red is a common problem during the flowering stage of growth. Different factors influence this phenomenon. To maintain the optimal health of these plants, it is necessary to understand what causes this problem. If we know how to prevent this problem, we can easily control this phenomenon.