Strawberry plants have a hidden language, and their leaves are the key to deciphering their messages. If you know what to look for, these leaves can reveal crucial information about the plant’s health and the quantity of berries it will produce. Let’s delve into the secret world of strawberry leaves and unlock their secrets.
Undersides of Leaves
Have you noticed watery lesions on the back of your strawberry leaves? These are caused by a bacterial infection known as angular leaf spot. The bacteria, known as Xanthomonas fragariae, lurks in the plant’s vascular system and seeps out of these lesions. It thrives in wet or humid conditions and enters the plant through wounds or natural openings.
If you spot an infected plant at this stage, it’s important to separate it from healthy plants and keep it in dry conditions. You could consider using validamycin, an antibiotic, to treat the plant. However, the most effective solution for home growers is to remove the plant at the end of the season and allow the bacteria in the soil to die over winter. It’s worth noting that angular leaf spot has minimal impact on berry production.
White Fluffy Patches
Do you see white, fluffy patches on your strawberry leaves? This is a common fungal infection called powdery mildew. It primarily targets young leaves, flowers, and fruit. To combat this fungus, you can spray your plants once a week with a mixture of one part milk to two parts water. The milk not only kills the fungus but also nourishes the plant without harming beneficial bugs.
To prevent future powdery mildew problems, consider treating the entire bed with potassium bicarbonate. This treatment will help eliminate any lingering spores in the soil.
The Color Red
Red leaves on strawberry plants might simply indicate that the season is changing or that temperatures are dropping. In most cases, the leaves will regain their green color in spring. However, if the red leaves also have small purple spots, it’s likely a condition called leaf scorch. This signifies the plant’s edges drying up and turning brown. To address this issue, remove the infected leaves and weeds to improve airflow.
The Color Yellow
Yellow leaves on strawberry plants can be an indication of overwatering. These plants typically need around an inch of water per day. To avoid overwatering, check the moisture just below the surface of the soil. If the soil is excessively wet, hold off on watering until it becomes slightly damp. Keep monitoring the soil to determine when to water again. As the moisture level balances out, the yellow leaves will gradually return to their vibrant green color.
If the leaves turn uniformly yellow-green while remaining dark green, an iron deficiency may be the culprit. This is more common in hydroponic gardens. Consider using a foliar fertilizer to address the deficiency.
The Color Purple or Black
Irregular purple-black splotches on the top of strawberry leaves are older lesions caused by the angular leaf spot bacteria mentioned earlier. While this may resemble leaf scorch, it is important to note that leaf scorch is caused by a fungus. To manage this issue, separate infected plants from healthy ones and keep them in dry conditions. The antibiotic validamycin may help treat the plant, but removing it at the end of the season is the best solution to allow the bacteria in the soil to die off.
Dark purple to reddish spots with light-colored centers on young, tender leaves indicate a condition known as strawberry leaf spot. On the other hand, small, solid dark purple spots without light-colored centers are an early sign of leaf scorch infection. If left unchecked, the leaves will eventually turn red-orange and develop brown scorched edges. To prevent further spread, remove the affected leaves and ensure there is ample airflow between plants.
Shades of Brown or Tan
Burned leaf tips are often indicative of a boron deficiency. Consider foliar feeding to address this issue, but be cautious not to over-apply to prevent boron toxicity. If you notice brown edges resembling a fringe, this could be a sign of a calcium deficiency. Finally, brown edges with a red field and purple spots are markers of advanced leaf scorch. It is recommended to remove the affected leaves to improve airflow. Additionally, make sure to clean up the strawberry bed at the end of the growing season to prevent the fungus from wintering on fallen leaves. Starting fresh with new plants is advisable for severely infected older plants.
Gray to tan blotches on older leaves indicate a condition called leaf blotch. While the fruit produced by these plants is still edible, it may not look visually appealing. Unfortunately, there is no treatment for leaf blotch. However, you can prevent it by planting through plastic sheeting, which acts as a barrier to prevent the fungus in the soil from splashing onto the above-ground portions of the plant.
Remember, understanding the language of strawberry plant leaves can help you maintain healthy plants and enjoy a bountiful berry harvest. So pay attention to the signs the leaves are giving you, and let your plants guide you to success.
Image Source: Ames Farm Center