Did you know that over 40% of garden plants fail each year due to poor soil conditions? Simply put, healthy soil means you’ll have healthier plants; healthier plants ensure better and larger harvests. Who doesn’t want that? In this guide, we’ll explore the essential steps to test, amend, and maintain your soil for a flourishing spring garden.
1. Test Your Soil
The first step will be to test your soil, which can be done in a couple of ways:
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Professional Testing:
- Procedure: Take a soil sample to your local university extension office, where they will usually test for free, though sometimes a nominal fee may be charged.
- Tests to Request: Be sure to specify that you would like the pH, nitrogen (N), phosphorus (P), and potassium (K) levels tested. These are the three primary nutrients needed in the largest amounts. You may also want to request the secondary macronutrients that your plants will need to be the healthiest: calcium (Ca), sulfur (S), and magnesium (Mg). Finally, if you are an absolute perfectionist and want to ensure the very best performance from your vegetables, annuals, or perennial plants, you can have your soil tested for boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), zinc (Zn), and chlorine (Cl).
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DIY Soil Test Kits:
- Options: You can buy a relatively inexpensive soil tester. The Cadillac of test kits will test for plant-available nutrients, as well as nitrogen and pH values. Some will also measure the amount of sunlight in a certain area of your yard, which can be vitally important for plant performance.
- Cost: These soil test kits will usually cost between $10 and $35. They are well worth the money spent to obtain the garden of your dreams.
2. Amend Your Soil
Once you have tested your soil, you can start to amend it as needed. Depending upon your deficiency, there are natural and organic means to raise the nutrient levels, as opposed to chemical fertilizers. However, if you choose chemical fertilizers, pay attention to the NPK listed on the bag. Those three primary nutrients should be balanced unless, of course, your soil is depleted of one or more. Then you will want to choose a fertilizer that has the corresponding nutrients in higher amounts.
Though you can find those same nutrients in the air we breathe or the water we drink, those nutrients are not available to plants. Their nutrients must come from the soil. Let’s look at the primary nutrients your plants need to grow.
Nitrogen
Nitrogen is necessary for your plants to live. It is kind of like oxygen to the human body. No oxygen—no human. No nitrogen—no plants. The earlier you can catch this deficiency, the better response your plants will have to the fix.
Signs of Nitrogen Deficiency
- If your plants live and bloom or produce fruit, they will be smaller, lower quality, and less abundant.
- The lower leaves start to yellow. This can also be a sign of overwatering, but if you have ruled that out, it is time to test the amount of nitrogen in your soil.
- The yellowing creeps up the plant; it will eventually reach the top. At this point, the death of your plant will occur.
- Plants will grow slowly, experience stunted growth, and have smaller than average leaves.
How Do You Fix Nitrogen Deficiency?
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Add Composted Manure:
- Be aware that some manures are “hotter” than others and can result in burning. Rabbit droppings and chicken manure should definitely be composted at least 6 months prior to amending your garden soil. Cow, horse, and goat manure can be worked into the soil after the last harvest to over-winter, which will ‘cool’ it down. Be sure to remove any debris before adding any soil amendments. If you know your garden plants have been subject to diseases, do not compost the debris. If adding these manures in the spring just before planting, it is much safer to compost. You can also purchase already composted manure to add in the spring.
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Make Manure Tea:
- You can add manure to a bucket of water and just let it soak. Voila…manure tea! You can use this to add a boost of nitrogen during the growing season. The more diluted, the less nitrogen; test your soil first.
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Rotate Your Crops:
- Many plants use high amounts of nitrogen and can deplete it over the course of a single season. Rotating your crops to plant ‘nitrogen-fixing’ plants where ‘nitrogen lovers’ have previously been planted will enable the nitrogen to replenish over the next couple of growing seasons.
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Amend with Bone and Blood Meal:
- Available at your local farm store.
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Add Used Coffee Grounds:
- You can add these throughout the season with no harm to your plants or add them to your compost pile.
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Use Fish Emulsion:
- This naturally adds nitrogen to your soil.
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Amend with Alfalfa Meal:
- Usually available at your local farm store.
Plants That Love Nitrogen
- Corn
- Tomatoes
- Lettuce
- Spinach
- Cabbage
- Broccoli
- Sunflowers
- Blueberries
- Strawberries
Plants That Fix Nitrogen
- Legumes: Beans, peas, chickpeas, lentils, and soybeans.
- False Indigo: A member of the legume family.
- Sesbania: Can be grown as a cover crop and then used as green manure, being worked back into the soil to add nutrients and organic matter prior to planting your spring garden.
- Lupines: Adapt to even the poorest soils and attract pollinators, enhancing biodiversity in your garden.
- Leadplant: Often planted alongside vegetables. It is modest in size, while its silvery foliage and tiny purple blossoms make it aesthetically pleasing. It has particularly deep roots to improve the overall structure of your soil.
Phosphorus
Phosphorus is also a vital nutrient for plant health. This nutrient is involved in numerous processes within your plants, including energy transfer, photosynthesis, and respiration. Yes, plants breathe. Phosphorus aids your plants as they process the energy from the sun, keeping them healthy on a cellular level. Phosphorus deficiency can be caused by numerous factors, including, but not limited to, acidic soil, excess levels of other nutrients like zinc or iron, and certain soils such as sandy or peaty soils.
Signs of Phosphorus Deficiency
- Increased pest activity and susceptibility to diseases.
- Plants may not mature as quickly and may be stunted in growth.
- Reduced leaf size and a purple or red discoloration on stems, petioles (the stalk that attaches the leaf to the plant stem), or leaves.
- Leaves may exhibit reduced thickness and may drop.
- Lower yields and quality of flowers and fruits.
How Do You Fix Phosphorus Deficiency?
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Test and Adjust Soil pH Levels:
- Procedure: Test your garden soil’s pH levels. Adjust pH as needed, amending your soil in small stages to avoid drastic changes.
- Raising pH: Use lime-based products, baking soda, or wood ash.
- Lowering pH: Amend with sulfur or organic materials (compost, decomposed leaves, worm castings, mushroom soil, or manure).
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Improve Soil Condition:
- Sandy or Peaty Soils: Work in some compost or organic material.
- Compacted Soil: Amend with organic materials, working them well into the soil to improve root access to minerals.
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Check Soil Temperature:
- Procedure: Use a thermometer to check the temperature close to the roots. If below 59°F (15°C), it is too cold.
- Solution: Before transplanting, check soil temperature. In case of an unexpected cold snap after planting, water plants with warmer, room-temperature water to improve phosphorus uptake.
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Adjust Fertilizer Use:
- Preferred: Use organic materials as suggested above.
- Emergency: Use a balanced commercial fertilizer if necessary.
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Rotate Your Crops:
- Refer to the crop rotation guide below to ensure phosphorus levels are maintained.
Plants That Need a Lot of Phosphorus
- Cucumbers
- Spinach
- Eggplant
- Herbs
- Chives
- Peppers
- Brussels Sprouts
- Watermelon
- Carrots
- Tomatoes
- Cabbage
Rotate the Above Vegetable Plants With the Following
- Lettuce
- Marigolds (also a fantastic pest deterrent)
- Garlic
- Radishes
Potassium
Potassium, another vital macronutrient, is critical to healthy plant growth and development. It plays a role in the activation of numerous vital plant enzymes, protects plants from stress-induced damages, and helps regulate water uptake. Potassium also mitigates oxidative stress, which changes how flavonoids, phenylpropanoids, and other metabolites are synthesized within the plant.
Signs of Potassium Deficiency
- Slowed plant growth, indicating diminished root growth.
- Burnt leaf edges, a sure sign of insufficient potassium.
- Purple spots, almost as common as burnt leaf edges.
- Yellowing leaves, especially within the leaf’s margins on older and lower leaves, which will eventually spread to younger leaves, leading to plant death.
- Wilting leaves due to insufficient potassium, which helps create pressure in plant cells to prevent wilting.
How Do You Fix a Potassium Deficiency?
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Add Decomposed Banana Peels:
- Method: Add decomposed banana peels to your homemade compost. Placing banana peels directly in or on the soil is not effective as they take a long time to decompose and may attract pests.
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Use Wood Ash:
- Benefit: Wood ash is a source of potassium.
- Caution: It can adversely affect your pH levels. Test soil pH before amending with wood ash.
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Apply NPK Fertilizer:
- Note: This commercially-prepared, inorganic fertilizer quickly supplies potassium but cannot be used to grow organically and can harm the environment.
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Use Potash Fertilizers:
- Sources: Made from natural sources like manure, seaweed, compost, and potash ore.
- DIY Method: Harvest comfrey leaves, store them in covered containers, and wait for them to liquefy over several weeks. Pour the resulting brown liquid around your plants.
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Rotate Your Crops:
- Strategy: Plant low-potassium-consuming plants for the following couple of seasons after harvesting your high-potassium-consuming plants.
Plants That Crave Potassium
- Eggplant
- Green Beans
- Peppers
- Zucchini
- Carrots
- Kidney Beans
- Honeydew Melons
- Strawberries, Blueberries, Blackberries
- Spinach
- Tomatoes
- Potatoes, including sweet varieties
- Cucumbers
- Peas
Plants That Use Little Potassium
- Herbs
- Lettuce
- Succulents
- Turnips
- Beets
- Swiss Chard
Conclusion
This may seem like a lot of information to take in, but once you've tested your soil for its nutrient content and pH, you can easily navigate to the section that addresses that particular need. We suggest you bookmark this article or print it out and put it in your gardening journal. Your soil’s nutritional levels will change with each season, depending upon what you have previously planted and other conditions that can rob your plants of nutrients.
We’ve done the research for you; our goal is to make your gardening experience easy, rewarding, and highly productive.
If you ever have questions, you can create a ticket here or even call us at the number listed at the top of the page. You will also find FAQs that may address your question or concern. We are more than happy to help you succeed in your gardening endeavors…you just have to ask.
