Potash is a critical nutrient for healthy, productive gardens and farms. This form of potassium helps plants develop strong roots, resist disease, and produce abundant flowers and fruits. While naturally present in some soils, many areas are deficient and require potash supplementation to reach optimum fertility. Fortunately, there are many options for purchasing the potash your garden needs. This guide covers everything you need to know about buying this essential fertilizer ingredient.
What is Potash?
Potash refers to a number of potassium-rich salts, with the most common being potassium chloride (KCl). While naturally present in small amounts in some soils, most regions require additional potassium in the form of potash fertilizer. This primary macronutrient aids in key plant growth processes including water regulation, photosynthesis, and the production of flowers, fruits, and seeds. Deficiencies can result in weak, stunted growth and reduced yields.
Benefits of Potash Fertilizer
Adding potash to your garden provides a wide range of benefits
- Promotes robust root development
- Increases drought tolerance
- Boosts plant immune response
- Improves the flavor of produce
- Encourages blooming and fruiting
- Helps plants access other nutrients
Potash also enhances the quality and storage life of fruits like tomatoes and peppers. It simply provides essential nutrition that most soils do not supply sufficiently on their own.
Where to Purchase Potash
Potash fertilizers can be purchased from garden centers, hardware stores, farm supply retailers, and online in bagged or bulk forms. Here are some of the most common options:
Local Garden Stores
Most independent garden stores and nurseries sell potash in bags or buckets. Look for popular options like sulphate of potash, potassium chloride (KCl), or potassium magnesium sulphate (K-Mag/Sul-Po-Mag). The staff can provide advice on selecting the right potash product.
Hardware Stores
Home improvement and hardware stores like Home Depot, Lowe’s Ace Hardware and True Value carry an assortment of potash fertilizers. Offerings may include sulphate of potash, Muriate of potash (granular potassium chloride) and popular blends that contain potassium.
Farm Supply Stores
Rural farm supply retailers like Tractor Supply Co and Atwoods Ranch and Home sell potash in larger bags tailored to farmers and commercial applications, Both granular and liquid potash formulations are often available
Online Retailers
A wide selection of potash fertilizers can be ordered online through retailers like Amazon, Arbico Organics, or GrowOrganic.com. Potassium chloride, sulphate of potash and custom blended fertilizers with potash are just a few clicks away.
Types of Potash Fertilizers
There are a few main forms of potash fertilizer to choose from:
Potassium Chloride
Also called Muriate of Potash, KCl is the most commonly used potash fertilizer worldwide. It consists of 60-62% potassium and provides a highly concentrated source in an affordable form. It is usually applied prior to planting.
Sulfate of Potash
Containing 50% potassium and 18% sulfur, Sulfate of Potash releases more slowly than KCl. The sulfate form reduces soil salinity and acidity. It is ideal for chloride-sensitive crops.
Sulfate of Potash Magnesia
This provides two vital nutrients – potassium and magnesium. The sulfate form also lowers pH. Well suited for magnesium hungry crops like tomatoes, peppers, and cucumbers.
Potassium Nitrate
Contains 44% potassium along with nitrate nitrogen. Often used as a foliar spray or in hydroponic systems. Quickly soluble and available to plant roots and leaves.
Potassium Carbonate
Supplies 52% potassium in a highly alkaline form for adjusting overly acidic soils. Less common than other potash sources.
Blended Fertilizers
Many multi-nutrient fertilizers also contain potash, with percentages ranging from 5-20%. This allows balanced feeding along with potassium.
How Much Potash Do I Need?
Potash rates vary based on your soil conditions, the specific crops you are growing, and application method. A general recommendation is 1-2 lbs of actual potash per 100 sq ft. For potassium-loving crops like tomatoes, aim for 2-4 lbs per 100 sq ft worked into soil before planting. Have your soil tested to determine if you need less or more based on current potassium levels.
How to Apply Potash Fertilizer
Granular potash can be worked into soil prior to planting crops and gardens. It can also be side dressed around established plants. Liquid formulations are ideal for foliar feeding during the growing season. Apply according to label rates and reapply as needed based on soil tests.
Using the right type of potash fertilizer at the proper rate and optimal timing will provide a productivity boost to gardens and farms of all sizes. Look for quality potash products from reputable companies like Espoma, Down To Earth, Fox Farm or Dr. Earth.
Frequently Asked Questions About Purchasing Potash
What is the difference between potash and potassium?
Potassium is a nutrient absorbed by plants, while potash refers to a number of potassium-rich salts used in fertilizers. All potash fertilizers provide plants with vital potassium.
Can I use wood ash as a potash fertilizer?
Wood ash contains moderate amounts of potash along with calcium and other minerals. It can be used sparingly as a potassium source but the exact composition varies widely.
Is Muriate of Potash natural?
Muriate of potash (potassium chloride) is extracted from naturally occurring mineral deposits. It is then processed into granular fertilizer. Not considered organic, but an effective mined mineral potash.
What fruits and vegetables respond best to potash?
Tomatoes, peppers, leafy greens, broccoli, grapes, berries, and most fruiting crops have a high potassium demand. Ensuring adequate potash improves productivity and quality.
How do I know if I need more potash?
Soil testing every 2-3 years will reveal if your garden’s potassium level is sufficient. Signs of deficiency include stunted plants with yellow lower leaves and poor fruit set. A soil test is the best way to determine if additional potash is needed.
When should I apply potash fertilizer?
Incorporate granular potash into soil 2-3 weeks before planting annual crops and gardens. It can also be side-dressed later in the growing season. Foliar sprays work fastest to correct in-season deficiencies.
Is potash safe for organic gardening?
Yes, there are OMRI certified organic potash fertilizers, like Sul-Po-Mag or langbeinite, approved for use in organic production. Always verify a product’s organic status before applying.
Can too much potash burn my plants?
Excessive potassium levels can inhibit the uptake of other nutrients. Follow soil test recommendations and label rates carefully to avoid over-fertilizing with potash.
The Takeaway
Adding adequate potash or potassium to your garden fertilizing routine maximizes the yield, flavor, and disease resistance of fruits, vegetables, flowers and herbs. Locate quality potash fertilizers at garden centers, hardware stores, farm supply retailers or through online sources. With the proper selection and application of potash products, your plants will thrive and reach their full potential.