Peters Professional S.T.E.M.
Best micronutrient supplement for correcting deficiencies in ornamental container plants.
Peters Professional S.T.E.M. is a fully water-soluble fertilizer providing a broad spectrum of essential minor elements for "quick fixes" on container plants and corrective action for micronutrient deficiencies. It's ideal as a remedial foliar spray for ornamental plants like tropical foliage, flowering plants, cut flowers, and orchids. This product has been the industry standard trace element supplement for over 40 years, delivering micronutrients from sulfates that also offer supplemental sulfur. Ensure soil is moist before application to prevent potential plant injury.
$100.54
Owner Satisfaction
4.7
/ 5
Category Rank
50
/ 4409
#50 in Fertilizers
Price vs Category Average
+63%
Above average
Weight
25.
/ lb
Who it's for
- Professionals streamlining complex nutrient management schedules
- Gardeners seeking to prevent common nutrient deficiencies
- Growers managing plants in varying water pH conditions
Who should skip it
- Beginners looking for an all-in-one fertilizer solution
- Budget-conscious hobbyists prioritizing low upfront costs
- Casual gardeners avoiding complex dosing and calibration
Performance breakdown
Micronutrient Density
Comprehensive trace element profile addresses deficiencies with clinical precision.
Solubility Speed
Dissolves instantly for seamless integration into any fertigation system.
Foliar Efficacy
Rapid absorption makes this the gold standard for corrective foliar treatments.
Versatility
Adapts easily from tropical foliage to delicate orchids and vegetables.
Application Safety
Requires careful soil moisture management to avoid potential leaf burn.
Professional Reliability
Four decades of industry trust confirms its consistent performance results.
Key Specs
Weight
25 lb.
Sulfur (S) (Combined)
13.00%
Iron (Fe)
7.50%
Manganese (Mn) (Total)
8.00%
Boron (B)
1.35%
Copper (Cu) (Soluble)
2.30%
Zinc (Zn)
4.50%
Molybdenum (Mo)
0.04%
Features
- Industry standard trace element supplement
- Ideal for quick fixes on container plants
- Totally soluble for easy mixing
- Provides essential minor elements
- Sulfate nutrients add beneficial sulfur
- Effective as a remedial foliar spray
- Suitable for continuous feeding programs
What customers say
Consumers view Peters Professional S.T.E.M. as a benchmark for quality in micronutrient delivery. The most consistent feedback highlights its reliability and efficacy, noting substantial improvements in plant vigor and overall health across diverse growing environments. Users appreciate how easily the soluble formula integrates into established feeding programs, confirming its status as a dependable and essential tool for achieving predictable, high level results without complication.
Know before you buy
S.T.E.M. stands for Soluble Trace Element Mix. It is designed to correct micronutrient deficiencies in container plants and serves as a reliable remedial foliar spray when plants show signs of stunted growth or discoloration.
While it is suitable for continuous feeding programs, it is primarily a supplement for minor elements rather than a complete NPK fertilizer. It works best when used alongside your regular fertilizer program to ensure plants receive a full spectrum of nutrients.
Applying concentrated micronutrients to dry soil or directly to thirsty plants can lead to root or leaf burn. Moistening the soil or foliage first ensures the plant is hydrated and better able to absorb the nutrients safely.
Yes, it is effective for a wide range of ornamentals, including tropical foliage, flowering plants, cut flowers, and orchids. Because it is a potent trace element mix, always follow the recommended dilution rates to avoid over-application.
The sulfate form of these micronutrients provides high solubility, making them quickly available for plant uptake. Additionally, the sulfates provide supplemental sulfur, which is a vital secondary nutrient for chlorophyll production and overall plant health.
Yes, it is specifically formulated to be fully water-soluble, making it an excellent choice for foliar application. This method allows for rapid absorption, which is ideal when you need a quick fix for visible nutrient deficiencies.
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