10 Natural Fertilizers: Pep Up Plants Midseason


Fertilizing vegetables mid-summer gives plants a boost

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Keep plants pumping out the flowers and fruit with midseason fertilizing. But if you just can’t afford another trip to the garden center for yet another bag of fertilizer, here are 10 natural fertilizers, many of which you may have right on hand.

If your plants are beginning to look a bit shabby and tired you can’t really blame them. They have been working hard for you all season and it is time for you to say thank you by giving them an energizing drink.

Don’t stop fertilizing now! This is especially important for heavy feeders such as tomatoes, peppers, corn, squash, melons and cucumbers. Broccoli, cabbage, beets and carrots can also use extra nutrition.

Here are some free natural fertilizers found right in your home.

  1. Coffee grounds and tea leaves – Soak the used grounds and tea bags for a week or so and water your plants with the weakened brew. It will pep them right up! Especially good for acid-loving plants, tomatoes, and roses. Learn more about using coffee grounds!
  2. Love a boiled egg? Your plants will love the calcium-rich water. Let it cool and use it on your tomatoes.
  3. Cleaning the fish tank? Save the aquarium water for your plants! It is high in nitrogen thanks to the fish poop.
  4. Don’t salt the water when you boil pasta and you can use it on your plants. It contains starch and trace amounts of nutrients your plant roots will soak up.
  5. Likewise don’t salt the water when you cook vegetables or boil corn. Along with sugary starches it contains loads of vitamins and minerals that have leached out of the veggies.
  6. Potato water adds a shot of potassium and carbohydrates to support soil microbes. It is excellent to use on fruiting and flowering plants.
  7. Dandelions also provide potassium. Fill a bucket with them while you are weeding, add water and let them soak for a few weeks. Or use grass clippings to make a nitrogen-rich liquid fertilizer. For more info on weed tea fertilizers see this previous post. www.almanac.com/fertilizer-tea-plants-weeds-and-grass
  8. Banana peels are another throwaway you can chop up and soak for a week or so. The banana broth supplies a hit of potassium, phosphorus, and calcium your tomatoes and peppers will put to good use. Learn more about using banana peels and other food waste in the garden!
  9. Beer is an excellent drink for your plants but seriously who is going to waste perfectly good adult beverages on their garden! Instead mix up a home brew equivalent from a packet of yeast, a tablespoon of sugar, and a quart of warm water. Let it sit for 2 hours in a warm dark place until it gets good and foamy. Dilute it in 3 gallons of water and propose a toast to your plants good health! It contains nitrogen, amino acids, and enzymes that strengthen disease resistance and encourage plant growth and fruit production.
  10. Compost, of course, is an excellent side-dressing to put around your plants but adding a shovelful of compost or rotted manure to a bucket of water and letting it mellow for a few days will make a liquid compost or manure tea that gets the nutrients to the plants faster. Feeder roots are near the top of the soil and they can immediately drink it in. For a fancy compost tea, check out this post

How to Apply Fertilizer

Applications of these homemade fertilizers give plants what they need to produce well. Just sidedress your plants, i.e., apply fertilizer alongside your row of crops or ring each plant with a narrow band of fertilizer. Apply 3 to 4 inches from stem of the plant; don’t get too close. Gently mix the fertilizer into the soil with your hands or a hand cultivator, then water.

Timing is important.

  • Your tomatoes, peppers and squash need this boost after flowering, and then again 4 weeks later.
  • Broccoli and cabbage can be fertilized beginning about 4 weeks after planting and every 2 to 3 weeks afterward.
  • Carrots and other root crops can be fertilized after thinning.

Replace nutrients that have gone into making the fruits and vegetables you have been harvesting this summer will keep them nourished and productive. These natural fertilizers are easy to make, kind to the environment, and most of the ingredients are readily available things you might be throwing away or tossing on the compost pile!

Learn about fertilizer tea made of weeds and plants.

About The Author

Robin Sweetser

Robin has been a contributor to The Old Farmer’s Almanac and the All-Seasons Garden Guide for many years. Read More from Robin Sweetser

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