Whether you’re getting ready to plant flowers & veggies or trees & shrubs, you might be asking yourself, “How much fertilizer should I use?”
What’s the right type, amount, and proportion of fertilizer to use for your container, raised garden bed, or lawn? It’s a big question to answer, so let’s tackle the very first part of it.
What type of fertilizer do you want to use?
Depending on what type of fertilizer you use, your needs will vary. But what are the different types of fertilizer and how do they differ?
There are three main categories of fertilizer — organic, chemical, and slow-release — and each category contains its own special (and rather long) list of brands and sub-categories.
- Organic fertilizer is made from plant or animal by-products (things like fish meal, bat guano, chicken manure, kelp meal, bone meal, etc)
- Chemical fertilizer is made from inorganic materials of wholly- or partially-synthetic origins (things like potassium nitrate, ammonium sulfate, urea, etc)
- Slow-release is often a chemical fertilizer that uses technology to slowly release the fertilizer into the soil over a specified period of time (from 1-month to 1-year)
So many fertilizer choices!
There are so many different types, blends and mixes of fertilizer to choose from! For example, there’s both dry and liquid fertilizer. It could be made of animal manure, shellfish meal, rock phosphate, or some other type of material, and each material should help bring about a different outcome. That outcome could be anything from conditioning the soil (manure) to stimulating the roots (phosphate).
On top of this, if you selected a slow-release fertilizer, you shouldn’t need to fertilize as often — which means you should require less fertilizer than if you selected a traditional fertilizer. This is because it releases nutrients slowly, over time. But just like the other types of fertilizer, slow-release fertilizers are offered by many brands and can be chosen based on where it’s going — for example, grass vs. vegetable gardens vs. flowerbeds.
Long story short, there’s a lot of noise out there when it comes to fertilizer, and you can’t exactly answer the question, “How much fertilizer should I use?” until you’ve figured out what brand and type of fertilizer you want to use.
What happens once I know what fertilizer I want to use?
After you’ve established what type of fertilizer you want to use, then you need to do some measurements and calculations.
We’ve talked about this before in our article that answers the question, “How much fertilizer do I need in my raised garden bed?” But to recap, you first need to identify how big your area is — length X width X height. Afterward, you need to figure out the volume, and then from there, you need to break that apart by proportions and also by how often you’re fertilizing. If you’re not careful during this part, you could end up spending more than you should and/or getting products you don’t even need (you might even manage to pick up products that could do more harm than good).
To dig a little deeper, let’s take a look at lawn fertilizer:
- You’ve already measured your lawn (length x width) to figure out you have 932 square feet of lawn. A lawn fertilizer bag you’ve found is 18lbs and covers 1,500sqft. Heres how to do the math:
- The lawn fertilizer covers (1500/18) 83.33 sqft per pound
- Your 758 sq. ft. of lawn will need (932/83.33) 11.18 pounds
Now things can get really tricky if the only measuring device you have around is a measuring cup or ol’ reliable (aka, your hand). If this is the case (which it probably is), how many cups is 11.18 pounds? Good question.
Even for experienced gardeners, this process can be complicated. And even if you are blessed by the math gods with number-crunching skills and you’re able to figure out how many cups of fertilizer you’ll need, we’re still not done.
Here’s the problem: fertilizer is sold in pounds, not cups. So if you need 32 pounds of fertilizer, how do you know which size fertilizer bag to buy? That’s right — no one knows (except Planting Pal, of course).
Blah, blah, blah … just tell me how much fertilizer to use.
If it seems like we didn’t answer the question, “How much fertilizer should I use?”, that’s because we didn’t. To answer that question, we’d need specifics, as we touched on previously. Specifics like — how big is your area, what type of fertilizer do you need and want, and how often do you actually want to fertilize.
This question is a big question because it involves a lot “stuff” — like types, options, math, and sometimes, your local area (what is readily available and what suits your environment?).
However, we can give you one simple answer to this convoluted question — use Planting Pal.
Planting Pal is an amendment calculator that uses the recommendations of local garden centers to get you the right product and quantities you need to successfully plant. Simply input your location and your measurements and Planting Pal will do the rest of the work for you — no math, no guessing, no grey areas.
Gardeners, launch Planting Pal now.
Garden centers & retailers, get started for free.
Product manufacturers, become a sponsor.
P.S. Already using Planting Pal and don’t see your favorite Garden Center? No problem! It’s free for them to join. Help them help you by spreading the word about Planting Pal.