Achieving a lush, green, and weed-free lawn is the dream of many homeowners. Two popular products often considered for this goal are Milorganite, a revered organic fertilizer, and the ubiquitous “Weed & Feed” products, which combine fertilizer with herbicides. While both aim to improve turf health and appearance, their distinct formulations and mechanisms of action raise important questions about their combined use. Can these two powerful allies work in harmony, or does their simultaneous application create more problems than solutions? This article will delve into the intricacies of using Milorganite alongside Weed & Feed, providing practical guidance on timing, application, and best practices to help you cultivate a vibrant lawn without compromising its health or your efforts.
Understanding the players: Milorganite and weed & feed
Before considering how to combine these products, it is essential to understand what each brings to your lawn care regimen. Milorganite is a slow-release, organic nitrogen fertilizer derived from heat-dried microbes. It boasts a nutrient analysis of 6-4-0 (nitrogen-phosphorus-potassium) and is particularly rich in iron, which contributes to its renowned deep greening effect. Its slow-release nature means nutrients are delivered gradually over several weeks, reducing the risk of nitrogen burn and promoting steady, sustainable growth. As an organic product, it also contributes to soil health by feeding beneficial microbes.
Conversely, “Weed & Feed” is a broad category of products designed for a dual purpose: fertilizing the lawn and controlling weeds. The fertilizer component typically contains fast-release nitrogen for quick green-up, often with varying levels of phosphorus and potassium. The weed control aspect comes from herbicides, which can be either pre-emergent (preventing weed seeds from germinating) or post-emergent (killing existing weeds). These products are often synthetic and designed for specific weed types and application timings. The fundamental difference lies in Milorganite’s organic, slow-release nutrient delivery and Weed & Feed’s often synthetic, faster-acting fertilizer combined with a targeted herbicide.
The challenge of combining: Why timing and product types matter
The primary challenge in using Milorganite with Weed & Feed stems from their different chemistries, release rates, and intended purposes. Applying them simultaneously or too closely can lead to several undesirable outcomes. One significant concern is over-fertilization, particularly nitrogen burn. Many Weed & Feed products contain a substantial amount of fast-release nitrogen. Adding Milorganite, even though slow-release, on top of this without proper intervals can lead to an excessive nitrogen load, potentially scorching the grass or promoting weak, rapid growth that is more susceptible to disease and pests.
Furthermore, the herbicide component of Weed & Feed needs specific conditions to be most effective. Pre-emergent herbicides need to form a barrier in the soil before weed seeds germinate, often requiring watering in. Post-emergent herbicides are typically absorbed by existing weed foliage and may require the weeds to be actively growing for optimal uptake. The nutrients from Milorganite encourage overall plant growth, which can sometimes interfere with how certain herbicides are meant to work or simply provide an unnecessary nutrient boost when the focus should be on weed eradication. Moreover, simply “dumping” both products without thought can be an inefficient use of resources, potentially washing away valuable herbicides or nutrients before they can be fully utilized.
Strategic application: When and how to integrate
The safest and most effective approach to combining Milorganite with Weed & Feed is to apply them separately, allowing adequate time between applications for each product to work as intended. The specific timing will largely depend on the type of Weed & Feed product you are using (pre-emergent or post-emergent) and your lawn’s seasonal needs.
For pre-emergent weed & feed:
- Apply your pre-emergent Weed & Feed in early spring when soil temperatures consistently reach 50-55°F, before crabgrass and other annual weeds germinate. Water it in thoroughly as directed on the label to activate the herbicide barrier.
- Wait approximately 2 to 4 weeks before applying Milorganite. This allows the pre-emergent herbicide to establish its protective barrier and gives your lawn a chance to absorb the initial nutrients from the Weed & Feed. Milorganite will then provide a steady, long-lasting feed for sustained health and color.
For post-emergent weed & feed:
- If your primary concern is existing broadleaf weeds, you might apply Milorganite first to promote healthy grass growth. Healthy turf can naturally outcompete some weeds.
- Wait 2 to 3 weeks after applying Milorganite. Then, apply a post-emergent Weed & Feed when weeds are actively growing, usually on a calm day when rain is not expected for 24-48 hours. Ensure the grass is dry before application, and avoid mowing immediately before or after to allow the herbicide to be absorbed by weed foliage.
- Alternatively, if weeds are widespread, apply the post-emergent Weed & Feed first. Once weeds show signs of wilting or dying (typically 1-2 weeks), then apply Milorganite to invigorate the recovering turf.
Here’s a simplified guide for common scenarios:
| Season/Goal | First Application | Wait Interval | Second Application | Key Considerations |
|---|---|---|---|---|
| Early Spring (Pre-Emergent) | Weed & Feed (Pre-E) | 2-4 weeks | Milorganite | Activate pre-emergent first; Milorganite provides sustained feed. |
| Late Spring/Summer (Existing Weeds) | Milorganite | 2-3 weeks | Weed & Feed (Post-E) | Promote healthy turf; then target weeds when actively growing. |
| Late Fall (Winterization/Weed Control) | Milorganite | 3-4 weeks | Weed & Feed (Fall-specific) | Milorganite for root strength; fall Weed & Feed for cool-season weeds. |
Important considerations and best practices
Beyond timing, several other factors contribute to the successful integration of Milorganite and Weed & Feed into your lawn care routine. Always begin with a soil test to understand your lawn’s specific nutrient deficiencies and pH levels. This data is invaluable for customizing your fertilization strategy and determining if any additional nutrients are needed beyond what these products provide. Moreover, always read and strictly follow the label instructions for both Milorganite and your chosen Weed & Feed product. Herbicide labels, in particular, contain critical information regarding application rates, environmental conditions, and safety precautions that must be adhered to for effectiveness and safety.
Proper watering is also paramount. Most Weed & Feed products, especially those with pre-emergents, require watering to activate the herbicide. Milorganite, while not needing immediate watering to avoid burn, does rely on moisture to break down and release its nutrients. After applying either product, ensure your lawn receives adequate water, either from rain or irrigation, according to product directions and your lawn’s needs. Finally, consider your specific grass type. Different grasses have varying nutritional requirements and sensitivities to herbicides. What works for a cool-season fescue might not be ideal for a warm-season Bermuda. By paying attention to these details, you can significantly enhance the efficacy of your efforts and cultivate a healthier, more resilient lawn.
Navigating the world of lawn care products can seem daunting, but when it comes to using Milorganite with Weed & Feed, understanding their individual characteristics and applying a strategic approach is key. The fundamental takeaway is that while these products can both contribute to a beautiful lawn, their concurrent application is generally not recommended. Instead, prioritizing separate applications with appropriate time intervals between them allows each product to perform optimally without counteracting the other. Whether you’re aiming to prevent weeds from germinating in the spring or tackle existing broadleaf invaders, thoughtful planning, adherence to label instructions, and an understanding of your lawn’s specific needs will lead to the best results. By integrating these practices, you can successfully leverage the benefits of both organic feeding and targeted weed control, ultimately achieving the vibrant, healthy turf you desire while minimizing potential pitfalls.