Summer Plant Nutrition

 

Understanding Plant Nutrition in Summer

Before we dive into specific fertilizers, let us talk about what plants need during the summer. Summer weather brings unique challenges and opportunities for plant growth. The intense sunlight drives photosynthesis, the process where plants convert light into energy. This process demands a lot of nutrients. Warm temperatures also speed up plant metabolism, leading to faster growth and, consequently, a greater need for essential elements.

Now, the basics:

Every garden fertilizer lists the three major ingredients on the front of the container, in this order: Nitrogen, Phosphate, and Potash. The first number on the label is always Nitrogen. Nitrogen promotes plant growth. The second number is Phosphate. Phosphate plays a major role in rooting and blooming. The third number is Potassium. Potassium plays a key role in overall plant development. Comparing organic and inorganic fertilizers side by side, organic fertilizers contain numbers such as 5-7-3 or 2-5-3. Inorganic fertilizers will typically have higher numbers, such as 11-15-11 or 9-58-8.  The number represents the percentage of each major component in the package.  

There are several types of fertilizers to choose from, each one with its own advantages. The best choice for you depends on your plants, the structure and health of your soil, and your gardening preferences.

Organic vs. Inorganic Fertilizers

The choice between organic and inorganic fertilizers is a matter of personal preference and gardening philosophy. Organic fertilizers are derived from natural sources, such as compost, manure, and bone meal. They improve soil health, support beneficial soil organisms, and release nutrients slowly. They often contain mycorrhizae, which improves the soil rhizosphere, encouraging better nutrient uptake. Inorganic (or synthetic) fertilizers are manufactured from chemicals. They provide readily available nutrients and can be formulated to meet specific plant needs. 

Organic Fertilizers offer slow-release nutrients as well as improved soil health, support beneficial organisms.

Inorganic Fertilizers tend to be fast acting, but do not offer soil micro biome support.

Both organic and inorganic are available in liquid and granular form. 

Matching fertilizers to plant needs

The summer heat can also impact nutrient availability. It’s important to avoid overwatering, as this can leach nutrients out of the soil. High temperatures might also affect the soil’s microbial activity, which is crucial for breaking down organic matter and releasing nutrients. Therefore, it’s essential to not only provide the right fertilizer but also to maintain proper soil health and watering practices.

Summer Fertilizing Guidelines

Watch the temperature: Avoid fertilizing when temperatures consistently exceed 85°F to 90°F. During extreme heat, plants shift into survival mode and are less able to absorb and use added nutrients effectively.

Hydrate before fertilizing: Water your garden thoroughly before applying fertilizer. Moist soil helps protect roots by slowing nutrient uptake and reducing the risk of fertilizer salts causing root burn.

Time it right: Apply fertilizer during the cooler parts of the day, such as early morning or evening. Cooler conditions help reduce plant stress and allow nutrients to be absorbed more effectively. 

Shift the N-P-K ratio: In midsummer, reduce high-nitrogen fertilizers because they can encourage weak, heat-sensitive foliage. Choose formulas with more phosphorus and potassium to support stronger roots, better blooms, and healthy fruit development.

Always follow package directions.

Never double fertilize. No exceptions. If you are using a slow-release fertilizer such as Osmocote to feed your hanging baskets or container plants, do not use any other fertilizer on them, organic or non-organic. The same is true if you are using a granular or water-soluble fertilizer, do not double feed your plants. 

Mulch matters.  For plants in the ground, use an organic mulch to help retain moisture and stabilize soil temperatures.