When it comes to the health of your strawberry plants, the leaves are a good way to tell how your strawberries are doing. Healthy strawberry leaves are usually a light or dark green color, so red colored leaves are a warning sign that something may be wrong with your strawberry plant.
Your strawberry leaves are turning red because they have a nitrogen deficiency. Nitrogen is a very important element for photosynthesis. Without enough nitrogen, a strawberry plant’s growth will be stunted, resulting in smaller strawberries.
This information probably sparked some questions about what you can do to help your strawberry plant get enough nitrogen and what you can do to prevent it from happening in the future. I’ve written this article to help you with exactly that.
Why does your strawberry plant have nitrogen deficiency?
The most probable cause of a nitrogen deficiency in your strawberry plant leaves is simply that there isn’t enough nitrogen in the soil it’s growing in. A lack of nitrogen in the soil can be caused by a few things:
- Leaching. This refers to the loss of water-soluble nutrients (such as nitrogen) in soil due to rain or excess watering.
- pH level. Nitrogen is mostly available in neutral soil, which is at around a pH level of 7.0. If the soil has a strong acidity or alkalinity, it will cause a problem with nitrogen availability.
- Excess carbon. When there is a lot of carbon in the soil, microorganisms will need more nitrogen to be able to break this carbon down, taking it away from the plants. Some high-carbon materials to be aware of are sawdust, straw, and pine needles. If these are in the soil or compost you use, it could throw off the carbon to nitrogen ratio.
Testing the Soil of Your Strawberry Plant
The best way to be sure that you’re dealing with a nitrogen deficiency is to test your soil. There are a few different ways you can go about this.
You can buy a self-test kit online or at a local gardening center, or you can send a sample off to a lab such as The UMass Soil and Plant Nutrient Testing Lab or this Whitetail Institute Laboratory Soil Test Kit. Here are at-home testers to consider:
|Luster Leaf 1601 Rapitest Test Kit||This test comes with four separate testers for pH, nitrogen, potassium, and potash. It’s inexpensive and a good way to get a basic reading.|
|Luster Leaf 1605 Digital Soil Test Kit||This test is a digital reader, which can be great if you find it hard to accurately compare other tests to charts. It comes with color-coded tubes that pop into the device, and it will show you results with different lights.|
While at-home testing kits are great for quick, efficient results, they don’t always give you the full picture as to what is going on in your soil. They give you base-line readings, which are great for giving you a basic understanding of what your soil may need. However, if you want a specific and detailed reading of your soil, it is best to send it off to a lab.
How Does Nitrogen Deficiency Affect Strawberries?
Nitrogen is a pillar element for plants. It is a major component of chlorophyll, which is needed for producing sugar from water and carbon dioxide during photosynthesis.
Nitrogen is also an important component of amino acids that build proteins to aid in plant growth and structure. Without these proteins, plants would wither away and die.
If your strawberries aren’t growing to the proper size, it can mean a lackluster harvest. The total volume of strawberries you do harvest may also go down, creating a need for more strawberries overall to fit your needs.
What To Do If Your Strawberries Are Nitrogen Deficient
A good way to get nitrogen back into your soil is to use a fertilizer high in nitrogen, or N. This can be achieved by both organic and synthetic options. If you don’t feel like making your fertilizer, there are plenty of commercial options you can try.
If you do end up buying fertilizer, it’s important to know the NPK ratio of the fertilizer you use. An NPK ratio tells you how much nitrogen (N), phosphorus (P), and potassium (K) is in the fertilizer. For nitrogen-deficient soil and plants, you want to make sure the first number in the ratio is high.
Using organic nitrogen fertilizers for your strawberry plants is a good choice if you want to go chemical-free. Here are some examples of nitrogen-rich materials you can use:
- Chicken manure. NPK can range from 3 – 2.5 – 1.5 to 6 – 4 – 3.
- Blood meal. NPK of 12 – 0 – 0.
- Feather meal. NPK of 13 – 0 – 0. Great source of nitrogen!
- Fresh lawn clippings. NPK of 4 – 0.5 – 2.
- Human urine. It seems weird, but human urine has an NPK ratio of 11 – 1 – 2.5!
Synthetic nitrogen fertilizers are man-made and often contain urea. Urea is an excellent source of nitrogen with an NPK of 46 – 0 – 0. Here are some urea fertilizers to consider:
However, it is also important to know that synthetic fertilizer needs to be applied repeatedly during the season since they act quite quickly and are easily broken down in the environment.
You don’t want to apply it too often, though. When you apply it faster than the plants can take in, it’s converted to nitrate by bacteria. This nitrate can be flushed from the soil by rain, and the runoff can pollute nearby water sources. Nitrification also produces a small amount of nitrous oxide, which hurts the ozone layer and contributes to the greenhouse effect.
Is there too much nitrogen in your soil?
If your strawberry plants are getting too much nitrogen, it can cause excessive growth. Too much of a good thing will adversely affect your strawberry plant:
- Flavor. Bigger strawberries can mean diluted flavor.
- Strength. Bigger strawberries can stress and weaken the plant stems.
- Health. Excess nitrogen makes your plants more prone to pests and diseases.
To avoid giving your plants too much nitrogen, it’s important to know when your strawberries need more or less nitrogen. Strawberry plants have a higher nitrogen demand in early spring and in late fall.
Leaf Scorch on Your Strawberry Plant
If you notice that your strawberry plant has purple-ish spots as well as red leaves, this is a sign of leaf scorch, a type of fungal infection. This infection can affect the whole plant, including the fruit, causing unsightly blemishes on your strawberries.
It is important to try and control leaf scorch so the infestation doesn’t become too severe, which can cause plant death. It thrives in wet conditions, so don’t let your soil become too wet. Remove the infected leaves and keep up with regular garden clean up and you should prevent it from spreading.
Should you be worried about strawberry leaves turning red?
If your strawberry plant’s leaves are turning red, there is no need for immediate panic. As in humans, nutrient deficiencies in plants are important problems but also easily fixed.
Luckily, there are many people that have had the same problem as you. There is an abundance of information on the internet for you to look over and learn how to take care of your plants like a professional.
Of course, you don’t want to leave it too long. Properly and quickly assessing the situation and fixing any problems is the key to keeping your strawberry plants healthy and fruitful.
Here are some of my favorite container gardening tools
Thank you for reading this post. I hope it helps you with your gardening needs. I’ve listed some tools below that can help you with container gardening. These are affiliate links so I’ll earn a commission if you use them.
Gardening Gloves – I find the Pine Tree Tools Bamboo Gardening Gloves really good for both men and women. It’s made from bamboo so helps absorb perspiration. They are also comfortable and fit very well.
Containers – You know picking the right container is crucial for your container gardening. I’ve written a detailed post on the best containers you can choose from. If you’re happy with a plastic container, you can check out the Bloem Saturn Planter.
Watering Can – This is a must-have tool when you’re growing plants in pots or grow bags. It helps to water the potting soil without splashing on the foliage. The Kensington Watering Can is stylish, strong, and can provide precision when watering potted plants.
Trowel – Garden Guru Trowel is my favorite because it’s durable and comfortable to use. My gardening friends really love having a trowel because they use it for digging soil, mixing fertilizer, moving seeds, leveling out the soil, mixing compost or mulch, and also dividing tubers
Bypass Pruner – I really like the Corona Bypass Pruner because it’s durable and gives a clean cut that helps plants recover faster. If you’re looking for something cheap, get the Fiskars Bypass Pruner that is really good as well.
To see an extensive list of the best container gardening tools gardeners recommend, check out this resource that I made for you.
Kevin is the founder of Gardening Mentor, a website that aims to teach people to grow their own food in a limited space. As a self-taught gardener, Kevin has spent several years growing plants and creating gardening content on the website. He is certified in Home Horticulture and Organic Gardening by expert gardeners from Oregon State University.