Which Plants Hate Epsom Salts? Understanding Magnesium and Sulfur Sensitivity in Your Garden

I remember the first time I heard about Epsom salts for gardens. My neighbor, bless her heart, was practically convinced it was the miracle cure for every plant ailment. She’d gush about bigger blooms, lusher leaves, and deterring pests, all with a sprinkle of those white crystals. Now, I’m a firm believer in the power of natural solutions, but something felt a bit off. I started noticing her prize-winning tomatoes looking a little… wilted, and some of her delicate flowers seemed to be struggling more than usual. That’s when I started digging, wondering, “Which plants hate Epsom salts?”

It turns out, my neighbor’s enthusiastic approach, while well-intentioned, wasn’t a one-size-fits-all solution. Epsom salts, chemically known as hydrated magnesium sulfate, are a fantastic source of magnesium and sulfur. These are indeed essential macronutrients for plant growth, playing vital roles in photosynthesis, chlorophyll production, and enzyme activation. However, just like with anything in life, too much of a good thing can be detrimental, and more importantly, some plants have specific dietary needs or sensitivities that make Epsom salts a definite no-go. My personal gardening journey has taught me that understanding plant needs is far more nuanced than a universal fertilizer application. This article aims to shed light on this often-overlooked aspect of gardening, helping you avoid common pitfalls and ensure your plants thrive, not just survive.

The Nuance of Epsom Salts in Gardening: Why “Universal” Fixes Can Backfire

The idea of using Epsom salts in the garden is rooted in sound horticultural principles. Magnesium is a central component of chlorophyll, the molecule that allows plants to capture sunlight for photosynthesis. Without enough magnesium, plants can develop yellowing leaves (chlorosis), particularly between the veins, a common sign of deficiency. Sulfur is another crucial element, involved in the synthesis of amino acids and proteins, and it contributes to the overall vigor and flavor of many plants. So, why the concern about which plants hate Epsom salts?

The answer lies in soil chemistry and plant physiology. Not all soils are deficient in magnesium, and some plants are naturally efficient at absorbing this mineral. Applying Epsom salts to soils that already have adequate or even high levels of magnesium can lead to an imbalance of other essential nutrients. This is often referred to as nutrient antagonism. For instance, an excess of magnesium can interfere with the plant’s ability to absorb calcium and potassium, both of which are critical for cell wall structure, water regulation, and disease resistance. Imagine trying to fill a bucket that’s already nearly full – any extra water will just spill over, potentially causing problems elsewhere.

Furthermore, some plants have specific preferences for nutrient uptake or are sensitive to the salt content in general. While Epsom salts are generally considered gentle compared to synthetic fertilizers, any soluble salt can potentially draw water away from plant roots in dry conditions, leading to stress. My own experience with sensitive herbs has shown me how quickly they can react to perceived imbalances in their environment, and that includes nutrient levels.

Identifying Plants Sensitive to Epsom Salts: A Closer Look

So, which plants are most likely to *hate* Epsom salts? While a definitive, exhaustive list is challenging to compile due to varying soil conditions and plant genetics, we can identify categories and specific species that are generally considered sensitive or where application is unnecessary and potentially harmful. These often include plants that prefer slightly acidic to neutral soils or those that are already well-supplied with magnesium from their native environment or soil type.

Generally, plants that *do not* benefit from or may be harmed by Epsom salts include:

Acid-loving plants: These plants, like blueberries, rhododendrons, azaleas, and hydrangeas, thrive in acidic soil with a pH between 4.5 and 6.0. Adding Epsom salts can potentially raise the soil pH, making it harder for these plants to absorb other essential nutrients like iron, leading to iron chlorosis (yellowing leaves with green veins).
Certain vegetables: While tomatoes and peppers are often cited as beneficiaries of Epsom salts, many other vegetables, especially those that prefer less-than-rich soil or have delicate root systems, might not appreciate the added magnesium. This can include root vegetables like carrots and radishes, as well as leafy greens that are prone to bolting or developing bitter flavors.
Most indoor houseplants: The potting mix used for houseplants often contains a balanced fertilizer, and it’s usually formulated to provide all the necessary nutrients. Over-applying Epsom salts can quickly lead to salt buildup in the soil, which can burn the fine roots of indoor plants and cause leaf tip browning or wilting.
Seedlings and young transplants: Young plants have underdeveloped root systems that are more vulnerable to the potential salt burn from Epsom salts. It’s best to focus on providing a gentle, balanced start for seedlings and only introduce amendments once they are established.
Plants in alkaline soils: If your soil is already alkaline (high pH), adding Epsom salts might not be beneficial and could further exacerbate nutrient imbalances, particularly for micronutrients like iron and manganese.

It’s crucial to remember that soil testing is your best friend here. Before reaching for the Epsom salts, understand what your soil actually needs. A simple soil test can reveal magnesium levels and pH, guiding you toward the most effective and plant-appropriate amendments.

The Science Behind Magnesium and Sulfur: Essential Roles and Potential Imbalances

To truly grasp which plants might hate Epsom salts, we need to delve a bit deeper into the roles of magnesium and sulfur in plant nutrition. Magnesium (Mg) is the central atom in the porphyrin ring of chlorophyll. Without magnesium, photosynthesis simply cannot occur. It also acts as an activator for many enzymes involved in carbohydrate metabolism, respiration, and nitrogen metabolism. Its deficiency symptoms are often first visible in older leaves as interveinal chlorosis, meaning the tissue between the veins turns yellow while the veins themselves remain green. In severe cases, the entire leaf can turn yellow or even develop necrotic spots.

Sulfur (S) is another essential macronutrient, often overlooked. It’s a component of the amino acids cysteine and methionine, which are building blocks for proteins. Sulfur is also involved in the formation of chlorophyll and is crucial for the synthesis of vitamins, glucosinolates (which contribute to the characteristic flavors of brassicas like broccoli and cabbage), and essential oils in plants like onions and garlic. Sulfur deficiency can manifest as a general yellowing of the plant, often starting with younger leaves because sulfur is not readily translocated within the plant like nitrogen.

The challenge arises when these nutrients are supplied in excess, or when their supply creates an imbalance with other nutrients. This is where the concept of nutrient ratios and soil chemistry becomes paramount. For example:

Magnesium-Calcium-Potassium Ratio: These are all divalent cations, meaning they carry a positive charge of +2. Plants absorb them in competition with each other. An excessive application of magnesium can inhibit the uptake of calcium and potassium. Calcium is vital for cell wall structure and membrane function, while potassium is crucial for water movement, enzyme activation, and disease resistance. An imbalance here can lead to weak cell structures, poor fruit development, and increased susceptibility to diseases.
Magnesium and Iron Interaction: In plants that prefer acidic soil, an increase in soil pH due to excessive salt application can reduce the availability of iron, leading to iron chlorosis, even if there is plenty of iron in the soil.
Salt Index: While Epsom salts have a relatively low salt index compared to many synthetic fertilizers, any soluble salt can increase the total dissolved solids (TDS) in the soil solution. This can create an osmotic imbalance, drawing water out of plant roots, especially under drought conditions or when applied too heavily.

My personal gardening experiences have reinforced this. I once tried to “boost” my container-grown herbs with a regular dose of diluted Epsom salts, assuming more magnesium meant healthier herbs. The result was stunted growth and yellowing leaves – a clear sign of nutrient imbalance, likely due to interfering with calcium or potassium uptake in the confined environment of the pot. It was a valuable lesson in understanding that plant health is a complex interplay of many factors, not just the addition of one nutrient.

Case Studies: Specific Plant Groups and Their Reactions to Epsom Salts

Let’s delve into some specific categories of plants and discuss their general sensitivities or lack thereof to Epsom salts.

Acid-Loving Plants: The Unwelcome Guest

Plants in this category are perhaps the most clear-cut examples of which plants hate Epsom salts. Think of the vibrant blooms of rhododendrons, azaleas, and hydrangeas, or the delicious tartness of blueberries. These plants have evolved to thrive in environments where the soil pH is naturally lower, typically between 4.5 and 6.0. This acidic environment is crucial for their ability to absorb essential micronutrients, especially iron, manganese, and zinc. These nutrients are often less available in neutral to alkaline soils.

Why Epsom Salts Can Be Problematic:

pH Shift: While Epsom salts are technically magnesium sulfate and not inherently alkaline, their application, especially in large quantities or repeatedly, can contribute to a less acidic soil environment over time. More importantly, if your soil already has a high pH, adding any soluble substance can disrupt the delicate balance and make it even harder for these plants to access iron.
Nutrient Lockout: The primary concern for acid-loving plants is not necessarily the magnesium itself, but the potential for it to interfere with iron uptake. Iron deficiency in these plants results in classic chlorosis: the leaves turn yellow between the veins, while the veins themselves remain dark green. This makes the plant look unhealthy and can significantly reduce flowering and fruit production.
Limited Need: Many plants that prefer acidic soil are naturally found in environments rich in organic matter, which often provides sufficient magnesium and other nutrients. Their natural habitat doesn’t typically involve high magnesium inputs.

My Take: I’ve seen gardeners try to force acid-loving plants to grow in less-than-ideal soil conditions by adding amendments. While some interventions might be necessary, reaching for Epsom salts is rarely the answer for these specific plants. Instead, focus on creating the right soil environment with things like composted pine bark, peat moss, or specific acidifying fertilizers if a soil test indicates a need.

Tomatoes and Peppers: The Popular but Potentially Misunderstood Beneficiaries

Tomatoes and peppers are frequently cited as plants that *benefit* from Epsom salts. The theory is that their heavy fruiting puts a strain on their magnesium reserves. Indeed, a magnesium deficiency can lead to blossom end rot in tomatoes (though this is primarily a calcium uptake issue, which can be exacerbated by magnesium imbalance) and reduced fruit production. However, this benefit is highly dependent on soil conditions and the specific plant’s needs.

When Epsom Salts Might Help:

Proven Deficiency: If a soil test confirms a magnesium deficiency, a light application of Epsom salts can indeed be beneficial for these plants.
Heavy Feeders: In heavily cropped gardens where soil nutrients are depleted, these plants might benefit from a supplemental dose.

When They Might Hate It:

Sufficient Magnesium: If your soil already has adequate magnesium levels, adding more can lead to the aforementioned nutrient imbalances, potentially hindering calcium and potassium uptake. This can paradoxically worsen blossom end rot or lead to other issues.
Container Growing: In containers, nutrients are more concentrated, and imbalances can occur more quickly. Over-application in pots is a common mistake that can lead to root burn and overall plant stress.
Alkaline Soils: In alkaline soils, magnesium is often less available, and adding more might not improve uptake and could disrupt other nutrient balances.

My Experience: I’ve found that for tomatoes and peppers, a balanced fertilizer that includes magnesium and other micronutrients is often a safer bet than relying solely on Epsom salts. If I suspect a deficiency, I’ll do a soil test first. If a deficiency is confirmed, I use Epsom salts very sparingly and infrequently, always diluting them and applying them as a soil drench rather than a foliar spray to avoid any potential leaf burn.

Leafy Greens and Root Vegetables: Generally Self-Sufficient

Many leafy greens like lettuce, spinach, and kale, as well as root vegetables such as carrots, radishes, and beets, generally do not require supplemental magnesium. Their nutrient needs are often met by a good quality compost or a balanced, all-purpose fertilizer. In fact, over-enriching the soil can sometimes lead to undesirable outcomes.

Why Caution is Advised:

Nutrient Balance: These plants often perform best in soils that are not excessively rich. Adding too much magnesium can disrupt the uptake of other essential nutrients, potentially affecting growth and flavor. For leafy greens, excessive nitrogen (which magnesium can influence) can lead to lush but less flavorful leaves or even increased susceptibility to pests. For root vegetables, it can lead to hairy roots or reduced root development.
Sulfur Content: While sulfur is beneficial, too much can also lead to imbalances.
Root Sensitivity: Root vegetables, by their nature, develop underground. Their delicate root systems can be sensitive to the osmotic effects of dissolved salts if Epsom salts are applied too heavily or too close to the plants.

My Approach: For these crops, I focus on building healthy soil structure with plenty of organic matter. They typically get enough magnesium and sulfur from compost and their regular feeding schedule without needing any Epsom salt applications. I consider them firmly in the “which plants hate Epsom salts” category, or at least, plants that don’t need it and might be harmed by it.

Herbs: The Delicate Divas

Many common culinary herbs, such as basil, mint, parsley, cilantro, and rosemary, can be quite sensitive to over-fertilization. They often prefer leaner soils and can develop more intense flavors when not overly pampered.

Reasons for Sensitivity:

Flavor and Aroma: High nutrient levels, including magnesium, can sometimes dilute the essential oils that give herbs their characteristic flavor and aroma.
Root Burn: The fine, delicate root systems of many herbs are easily damaged by excessive salt buildup in the soil. This can lead to stunted growth, wilting, and leaf browning.
Specific Needs: Many herbs are adapted to well-draining soils with moderate fertility.

My Personal Experience: I learned this the hard way with my basil. I’d tried giving it a little “boost” with diluted Epsom salts, and within a week, the leaves were tinged yellow, and the growth slowed to a crawl. It took several weeks of flushing the pot with clean water and adding a bit of compost to help it recover. Now, my herbs are much happier with just good soil and occasional light feeding.

Indoor Houseplants: A Recipe for Salt Buildup

For most indoor houseplants, the use of Epsom salts is generally unnecessary and often detrimental. The potting mix they are planted in is usually formulated to contain a balanced fertilizer, and it’s designed for good drainage and aeration.

Why It’s Risky:

Salt Accumulation: Unlike outdoor plants that are watered by rain, houseplants rely on us for watering. Over time, salts from fertilizers and amendments like Epsom salts can accumulate in the potting medium, leading to a condition known as “salt burn.” This manifests as brown, crispy leaf tips and edges, wilting, and stunted growth.
Pre-mixed Nutrients: Reputable potting mixes already contain the necessary macronutrients and micronutrients in appropriate ratios. Adding more magnesium can upset this balance.
Limited Flushing: It’s harder to “flush out” excess salts from a potted plant without potentially overwatering or leaching other essential nutrients.

Recommendations: If you suspect your houseplant might have a nutrient deficiency, it’s best to use a balanced, water-soluble houseplant fertilizer diluted according to package instructions. If you suspect salt buildup, the best course of action is to repot the plant in fresh potting mix or to leach the current soil by flushing it with large amounts of water until it drains freely from the bottom. For most houseplants, the question of “which plants hate Epsom salts” leans heavily towards “all of them” unless a specific deficiency is diagnosed and corrected carefully.

How to Use Epsom Salts Responsibly (If You Choose To)

Despite the sensitivities, there are times and places where Epsom salts can be a valuable tool in the gardener’s kit. The key is responsible, informed use. If you’ve done your homework, considered your soil type, and identified a potential need, here’s how to approach it:

1. Soil Testing is Paramount

Before you even think about applying Epsom salts, get a soil test. Most university extension offices offer affordable soil testing services. This will tell you your soil’s pH, its current levels of essential nutrients (including magnesium), and provide recommendations for amendments. This is the single most important step in determining if your plants actually *need* the magnesium and sulfur that Epsom salts provide, and crucially, if they can tolerate it.

2. Understand Your Plant’s Needs

As discussed, know which plants are generally sensitive. If you’re growing acid-loving plants, blueberries, or many delicate herbs, it’s best to skip the Epsom salts altogether. For plants like tomatoes, peppers, or roses where deficiency is sometimes suspected, a soil test is still your best guide.

3. Dilution is Key

Never apply Epsom salts in their dry, granular form directly to the soil around plants. Always dissolve them in water. A common dilution rate for soil application is 1 to 2 tablespoons of Epsom salts per gallon of water. For foliar feeding (spraying directly onto leaves), use an even more dilute solution, around 1 tablespoon per gallon, and apply in the early morning or late evening to avoid leaf scorch in the sun.

4. Application Methods

Soil Drench: This is the most common method. After dissolving the salts in water, pour the solution around the base of the plant, ensuring it moistens the root zone. Avoid getting the solution on the foliage, especially if you’re using a stronger concentration.
Foliar Feeding: For quick correction of a suspected magnesium deficiency, you can spray a diluted solution directly onto the leaves. Plants can absorb nutrients through their leaves, though this is usually a temporary fix. Apply on a cool, cloudy day or in the evening to prevent burning.
Frequency: Do not overdo it. For most plants that might benefit, applying a diluted solution once or twice during the growing season is usually sufficient, especially if your soil test indicated a mild deficiency. More frequent applications can lead to imbalances.

5. Consider the Context

Container Plants: Be extremely cautious with container plants. Their nutrient needs are more concentrated, and imbalances can happen quickly. Use very dilute solutions and infrequent applications.
New Plantings: Avoid applying Epsom salts to newly transplanted seedlings or young plants. Their root systems are still developing and are more susceptible to damage. Wait until they are established.
Soil Type: In sandy soils, magnesium can leach out more easily, potentially making applications more beneficial. In clay soils, magnesium is held more tightly, and deficiencies are less common.

My personal rule of thumb is this: If in doubt, don’t use it. There are many other ways to build healthy soil and provide nutrients, such as using compost, well-rotted manure, and balanced organic fertilizers. Epsom salts should be a targeted solution, not a blanket application.

Common Misconceptions About Epsom Salts in the Garden

The popularity of Epsom salts has led to a host of common gardening myths. Let’s debunk a few:

Myth: Epsom salts deter slugs and snails. While the granular form might create a slight physical barrier that some find inconvenient, slugs and snails will readily cross it, especially when moist. There are far more effective and less harmful methods for slug control.
Myth: Epsom salts are a cure-all for yellowing leaves. Yellowing leaves (chlorosis) can be caused by numerous issues, including nitrogen deficiency, iron deficiency, overwatering, underwatering, poor drainage, diseases, and pests. While magnesium deficiency *can* cause yellowing, it’s just one of many possibilities. Always diagnose the problem before treating it.
Myth: Epsom salts are a natural fertilizer. While magnesium and sulfur are natural elements essential for plant growth, Epsom salts are a chemical compound (hydrated magnesium sulfate). They are not a complete fertilizer; they only provide magnesium and sulfur.
Myth: You can never use too much Epsom salts. This is simply untrue. As we’ve explored, excessive use can lead to nutrient imbalances, salt burn, and harm to sensitive plants.
Myth: Epsom salts make flowers bigger and brighter automatically. While magnesium is essential for chlorophyll and photosynthesis, which indirectly supports flowering, the dramatic increases in bloom size and vibrance are often attributed to Epsom salts when other factors are actually at play, such as adequate watering, sunlight, and a balanced nutrient profile from the soil.

It’s important to approach gardening advice with a critical eye and always consider the specific needs of your plants and your soil conditions. Relying on scientific understanding and observation will serve you far better than adopting blanket solutions.

Frequently Asked Questions About Which Plants Hate Epsom Salts

How do I know if my plant actually needs magnesium?

Determining if a plant genuinely needs magnesium requires careful observation and, ideally, scientific confirmation. The classic symptom of magnesium deficiency is interveinal chlorosis, where the tissue between the leaf veins turns yellow, while the veins themselves remain green. This pattern typically appears first on older, lower leaves, as magnesium is mobile within the plant and can be translocated to newer growth when reserves are low. However, this symptom can be confused with other nutrient deficiencies or diseases. For instance, iron deficiency often presents similarly but usually starts on younger leaves. Nitrogen deficiency causes a more uniform yellowing of older leaves. The most reliable method is a soil test. A comprehensive soil analysis will not only tell you the magnesium level in your soil but also its pH and the levels of other essential nutrients, providing a complete picture of your soil’s fertility. This allows you to make informed decisions about whether Epsom salts are necessary or if other nutrient imbalances need to be addressed. Without a soil test or clear, consistent deficiency symptoms, it’s best to assume your plant has adequate magnesium.

Why are some plants more sensitive to salts in general than others?

Plant sensitivity to salts, including Epsom salts, stems from several physiological and ecological factors. Firstly, plants have varying abilities to regulate their internal water and mineral balance. Some plants, often those native to arid or semi-arid regions, have evolved sophisticated mechanisms to tolerate higher salt concentrations in their environment. They might excrete excess salts, compartmentalize them within cells, or have specialized root structures to minimize salt uptake. Conversely, plants adapted to consistently moist, nutrient-rich environments may have less robust salt tolerance mechanisms. Their root systems are often finer and more delicate, making them more susceptible to osmotic stress. When salts are present in the soil solution, they increase the solute concentration. This makes it harder for the plant’s roots to absorb water, as water moves from an area of lower solute concentration to higher solute concentration. If the soil solution is too concentrated with salts, water can actually be drawn out of the plant’s roots, leading to dehydration and damage, a phenomenon known as osmotic stress or salt burn. This is why seedlings, plants with fine root systems, and those grown in containers (where salt buildup is more rapid) are particularly vulnerable.

Is there a difference between using Epsom salts for soil application versus foliar feeding? Which is better for plants that hate Epsom salts?

Yes, there is a significant difference between soil application and foliar feeding of Epsom salts, and for plants that are sensitive, foliar feeding, if used at all, should be approached with extreme caution. Soil application involves dissolving Epsom salts in water and applying the solution around the base of the plant. The magnesium and sulfur are then absorbed by the roots from the soil. This method is generally slower acting but provides a more sustained release of nutrients. However, it also carries a higher risk of salt buildup in the soil over time, especially with repeated applications or in poorly draining conditions. Foliar feeding involves spraying a very dilute solution of Epsom salts directly onto the plant’s leaves. Plants can absorb nutrients through their stomata and leaf surfaces. This method is typically faster acting, as the nutrients are absorbed directly into the plant tissues. It can be useful for quickly correcting a visible deficiency. However, foliar applications are temporary, and the nutrients are not stored in the soil. For plants that “hate Epsom salts” or are sensitive to salinity, foliar feeding, even when highly diluted, still carries the risk of leaf burn, especially if applied during the heat of the day or if the concentration is too high. The salts can dehydrate the leaf tissue. Therefore, for sensitive plants, the best approach is to avoid Epsom salts altogether. If a magnesium deficiency is suspected and has been confirmed, and foliar feeding is considered as a last resort for a *very* tolerant plant, it must be done with extreme dilution (e.g., 1 teaspoon per gallon of water) and only during cool, overcast conditions. However, for plants that truly hate Epsom salts, no application method is truly “better”; avoiding it is the best strategy.

What are some natural alternatives to Epsom salts for magnesium and sulfur if my plants need them?

If your soil test indicates a need for magnesium and sulfur, and you wish to avoid synthetic sources or are dealing with plants that are sensitive to the salt content of Epsom salts, there are several excellent natural alternatives. For magnesium, consider using **dolomitic lime**. This is a natural soil amendment that contains both magnesium and calcium. However, it also increases soil pH, so it’s only suitable for soils that are acidic and can benefit from a pH boost; it would be detrimental to acid-loving plants. Another excellent organic source of magnesium is **magnesium-rich compost** or **aged manure**. Many organic fertilizers derived from natural sources, such as bone meal or alfalfa meal, also contain magnesium. For sulfur, **gypsum (calcium sulfate)** is a good source, and it also helps improve soil structure, especially in clay soils, without significantly altering pH. **Compost** is also a good source of sulfur. Certain organic fertilizers, like **blood meal** or **feather meal**, also provide sulfur along with nitrogen. Using these organic amendments not only provides the needed nutrients but also contributes to overall soil health, improving its structure, water retention, and microbial activity, which can indirectly help plants absorb nutrients more efficiently. These natural amendments tend to release nutrients more slowly and are less likely to cause the rapid osmotic stress associated with soluble salts like Epsom salts.

Can Epsom salts harm soil microbes or beneficial insects?

While Epsom salts are generally considered less harmful to soil microbes and beneficial insects than many synthetic fertilizers, excessive application can still have negative impacts. High concentrations of any soluble salt can disrupt the delicate osmotic balance in the soil, affecting the water content available to all living organisms, including beneficial bacteria, fungi, and micro-arthropods that are crucial for soil health. If salt levels become too high, they can stress or even kill some of these essential soil dwellers, reducing the soil’s natural fertility and its ability to break down organic matter. For beneficial insects, such as pollinators or predatory insects, direct contact with concentrated Epsom salt solutions could potentially cause harm, although this is less common than with broad-spectrum insecticides. The primary concern with Epsom salts is their effect on plant health through nutrient imbalances and salt stress, but we should not overlook their potential indirect impact on the wider soil ecosystem. Using Epsom salts judiciously, in diluted forms, and only when a specific need has been identified through soil testing, is the best way to minimize any potential harm to the beneficial life in your garden.

In conclusion, while Epsom salts can be a beneficial garden amendment for specific plants and under certain conditions, it’s crucial to understand that not all plants appreciate them. By identifying which plants hate Epsom salts and understanding the underlying reasons for their sensitivity, gardeners can make more informed decisions, leading to healthier, more vibrant gardens. Remember, observation, soil testing, and a nuanced understanding of plant needs are your most valuable tools.

Which Plants Hate Epsom Salts? Understanding Magnesium and Sulfur Sensitivity in Your Garden