Best Pumpkin and Squash Fertilizer – 9 Best Fertilizers for Pumpkins and Squash

Pumpkins mean fall in North America. I plant my pumpkin vines in the summer, so the pumpkins are ready for Halloween. Like many vegetables, pumpkins are considered heavy feeders. I can tell you from experience that without enough fertilizer, your pumpkin vines won’t produce nice pumpkins. You may wonder, “What is the best pumpkin fertilizer?” 

The best pumpkin fertilizer varies depending on the stage of life the pumpkin vine is in and the type of fertilizer you want to use. I have picked 9 premium fertilizers that will help you grow the best pumpkins possible. I also tell you when and how to use each fertilizer.

    Why Fertilize Your Pumpkins? 

    Producing a pumpkin takes a lot of time, space, water, and nutrients. It is unlikely that your soil contains all the nutrients your pumpkin vines need. Without fertilizer, you can’t grow a good pumpkin, whether you grow pie pumpkins or giant pumpkins. The vines just can’t produce a good pumpkin without fertilizer, and you waste all that time and space.

    Why You Should Invest in a Good Pumpkin Fertilizer?

    Cheap fertilizer is mostly filler. You have to put more of it down, so it really doesn’t save you any money. Pumpkins take a lot of room in the garden and take a lot of time to produce. Don’t waste the space and time to save a few bucks. Invest in one of the premium fertilizers listed below for the best results. 

    Picking the Best Fertilizer for Your Pumpkins

    Each fertilizer has three numbers on the front, separated by dashes. These numbers stand for the percentage of the fertilizer that has nitrogen, phosphorus, and potassium in it, in that order. You need all three nutrients to grow the vines and pumpkins.

    Pumpkin Vines Photo by Stephanie Suesan Smith
    Pumpkin Vines Photo by Stephanie Suesan Smith

    Nitrogen is needed by all plants to grow foliage, fruit, and seeds. If you do not have enough nitrogen, the vine and pumpkin can’t grow. Too much nitrogen encourages pumpkin vines to grow lots of vines and leaves but not grow pumpkins. Excess nitrogen can also burn leaves and roots. 

    Pumpkin Blossoms Photo by Stephanie Suesan Smith
    Pumpkin Blossoms Photo by Stephanie Suesan Smith

    Phosphorus helps the plant convert other nutrients into the things the plant needs to grow. A lack of phosphorous causes small blooms and weak growth. Too much can burn the plant and kill it. 

    Potassium is associated with the movement of nutrients, water, and carbohydrates throughout the pumpkin vine. Potassium also helps pumpkins mature. Without potassium, the plant won’t grow well. The leaves will be yellow on the edges and need lots of water. Too much potassium will encourage quick pumpkin growth and can make your pumpkins split, explode or fall off the vine before they are ripe. 

    Seeds versus Transplants

    Most authorities recommend buying transplants or starting your seeds inside about two months before the soil warms, so your pumpkins can start growing outside quickly. You can direct sow pumpkin seeds in the ground, but the soil temperature has to be at least 70 degrees F before the seeds will germinate. Pumpkins take around 120 days to be ready to harvest. Planting seeds may not leave enough time before the first frost to grow the pumpkins, especially if you are growing a giant pumpkin. 

    To start seeds inside, follow these steps.

    1. Sow seed starting mix in a tray that has drainage holes in it. 
    2. Wet the seed starting mix.
    3. Let the water drain out of the soil starting mix.
    4. Plant the seeds an inch deep.  
    5. Space the seeds five inches apart.  
    6. Water the soil often enough to keep it moist but not soggy.
    7. Once the seedlings have their first true leaves, fertilize every two weeks with a water-soluble fertilizer high in nitrogen, such as Pumpkin Juice 11-8-5 (listed below). 

    How to Fertilize Your Pumpkins?

    What nutrients you use to fertilize your pumpkins are as important as what type of fertilizer you use. In the first third of the season, concentrate on nitrogen-heavy fertilizers. After the vines are about ten feet long, switch to phosphorus-heavy fertilizers. Finally, use potassium-rich fertilizers during the last third of the pumpkin’s growth. Fertilize the whole length of the vine because the vines develop small feeder roots at the nodes and take up the fertilizer from them as well as the main root system   

    Start in the fall and follow these steps: 

    1. Till up a large area for the vines to a depth of six inches.   
    2. Spread six inches of compost over that area. 
    3. Work the compost into the tilled soil.   
    4. Take a soil test and send it to the soil lab in your area. 
    5. Fertilize according to the soil test recommendations. 
    6. Work the fertilizer into the top three inches of soil.
    7. Build a mound with soil that is ten inches in diameter and three to four inches tall. 
    8. Cover the entire area with straw or other mulch. 

    Before planting pumpkin seeds or transplants in the ground, follow these tips:

    How to side-dress fertilizer by Stephanie Suesan Smith
    How to side-dress fertilizer by Stephanie Suesan Smith
    1. Remove any mulch that hasn’t rotted over the winter. 
    2. Spread urea granules across the entire area the vines will grow. 
    3. Work the granules into the top three inches of the soil. 
    4. Water in the fertilizer. 
    5. Start seeds by planting three to five seeds one inch deep and two inches apart on the mound. 
    6. After the seedlings have two true leaves, thin to the strongest two seedlings on the mound by pinching off the other seedlings. Do not pull them, or you will disturb the roots of the strong seedlings. 
    7. If planting transplants, plant two transplants on opposite sides of the mound. 

    Every two to four weeks, side dress fertilizer (put it parallel to the vines but six inches away) along the entire length of the vine. 

    Fertilizer Needs Change

    The best pumpkin fertilizer changes depending on where in the life cycle of the pumpkin vine you are.   This is true whether you want to grow big pumpkins or pie pumpkins.   

    The first 55 days after the seedlings emerge or the transplants are planted, the vines need a nitrogen-heavy fertilizer. For the best pumpkins, pick the blooms off of the vine until it is ten feet long    

    Once the vines are long enough, allow the vine to bloom. At this point, the vines need a phosphorus-heavy fertilizer to promote good blooms and help the fruit to set.

    Once the fruit starts growing, the vines need a potassium-rich fertilizer until the pumpkins are picked. For giant pumpkins, thin the pumpkins to one pumpkin per vine. For smaller pumpkins, you can allow the vine to have more pumpkins per vine. 

    Liquid versus Granular

    Liquid fertilizers and granular fertilizers have the same nutrients. However, liquid fertilizer goes into the soil faster and is more readily available immediately. It also takes less water than granular fertilizer. However, granular fertilizer can release small amounts of nutrients over a long time. The fertilizer must be watered in to activate the granules. 

    Squash versus Pumpkin

    Technically, a pumpkin is a squash, so the best fertilizers for squash and pumpkins are the same at each stage of the vine’s life. 

    Best Pumpkin and Squash Fertilizers

    I have listed three fertilizers, each featuring nitrogen, phosphorous, or potassium, where it makes sense, so you will know the best fertilizer for each stage of a pumpkin’s life. 

    1. Cesco Solutions Urea  – Best Urea Fertilizer for Pumpkins

    cesco-solutions-urea

    Urea is a naturally occurring source of nitrogen. While it used to be derived from urine, most urea for vegetables is synthetic to avoid spreading disease. Spreading urea around before you plant seedlings gives them an initial burst of nitrogen to help them get established and grow.

    Cesco Solutions Urea is a great urea to use in the pumpkin patch. It is released slowly, so it feeds your pumpkin vine for a long time. I like this fertilizer because it is made of high-quality ingredients and is really pure. The granules are easy to handle, and I don’t get fertilizer all over me. Unlike many fertilizers, Cesco Solutions Urea is odorless and water-soluble. I spread it before I plant my transplants and work it into the first two or three inches of soil. Then, I water it in and plant my transplants. I know Cesco Solutions Urea will start my transplants off right. This fertilizer is not organic but is good enough that I have overlooked that. Because Cesco Solutions Urea does not contain phosphorus or potassium, I only use it when I first plant my transplants. It won’t support the vines when they bloom or set fruit.

    Pros:

    • Easy to use
    • Odorless
    • Water-soluble
    • Inexpensive

    Cons:

    • Doesn’t contain phosphorus or potassium
    •  Not organic

    Best Liquid Fertilizer for Pumpkins 

    There are three liquid fertilizers I use, depending on the stage of the lifecycle my pumpkin vines are on that day.  

    2. Pumpkin Juice 11-8-5 – Foliar Liquid Fertilizer with Essential Micro-nutrients for Pumpkins and Vegetables 

    Pumpkin Juice 11-8-5

    Pumpkin Juice is formulated just for pumpkins, so it contains everything the vines need to grow well and produce lots of pumpkins. I have not found another product formulated just for pumpkins. The Pumpkin Juice container has a measuring system built right into it, so I don’t have to fool with measuring cups. Mixing the liquid into water is not hard, and I don’t have to get any of it on me when I pour the solution around my vines. Although the container is more expensive initially than a ready-to-use product, the concentrate saves me money in the long term. Because one container makes many gallons of fertilizer, Pumpkin Juice uses less energy to produce and less petroleum in the plastic than a ready-to-use product.

    Pumpkin juice is a great fertilizer to use when starting pumpkin seeds indoors. I simply mix one ounce of Pumpkin Juice with a gallon of water and use it to water my indoor seedlings every two weeks after they grow their first true leaves. Once the seedlings are in the ground, I mix two ounces of Pumpkin Juice with one gallon of water. I pour Pumpkin Juice beside the whole vine. Because the Pumpkin Juice is in water, the roots take it up quickly and spread it to the entire vine. I don’t use this product after the blooms start because it can cause an overgrowth of foliage at the expense of flowers. While I would prefer an organic product, Pumpkin Juice is good enough to make up for containing synthetic ingredients.

    Pros:

    • Easy for the vines to take up
    • Formulated especially for pumpkins, so it has everything they need
    • Water-soluble
    • The container has a built-in measuring system
    • Buying concentrate saves money in the long run

    Cons:

    • Expensive initially
    • It can promote too much foliage if used after blooms start
    • Needs to be mixed at one ounce per gallon of water for young plants to avoid burning them
    • Needs to be mixed before use.
    • Not certified organic
    • Needs to be applied every 2 weeks

    3. Neptune’s Harvest Fish Fertilizer 2-4-1 

    Neptune's Harvest Fish Fertilizer 2-4-1 

    When it is time for my pumpkin to bloom, Neptune’s Harvest Fish Fertilizer becomes my go-to liquid fertilizer. It is easy to mix and certified organic. The cold press process protects the nutrients in the North Atlantic fish, seaweed, and kelp that make up the fertilizer. Because it is a liquid, Neptune’s Harvest is fast acting. It does require mixing and can be pricey. The solution is more dilute than many fish emulsions, so you use more of it for the same results. I think using concentrate is better for the environment than using a ready-to-use fertilizer because there isn’t as much packaging. Less packaging means less plastic in the landfill, too.

    I mix one ounce of concentrate with one gallon of water. While Neptune’s Harvest contains some nitrogen, it does not have an excessive amount. I have not had problems with excessive vine growth when using it. In addition to being a good source of phosphorous and potassium, Neptune’s Harvest has lots of micronutrients pumpkins need to make flowers and set fruit. 

    Pros:

    • Easy to mix
    • Water soluble
    • Certified Organic
    • Cold-pressed, so it doesn’t lose heat-sensitive nutrients
    • Fast acting

    Cons:

    • Has to be mixed into water to apply
    • Can be pricey
    • More dilute than some fish emulsions
    • Needs to be applied every 2 weeks

    4. Simply Silica 8oz Concentrate 

    Simply Silica 8oz Concentrate

    Simply Silica contains potassium silicate. I like this potassium-rich fertilizer for after the vine sets fruit. The bottle makes an incredible 47 gallons of solution, so it is very cost-effective. Since Simply Silica is water soluble, the pumpkin vine can take it up easily and use it immediately. I usually see an effect in my vines two or three days after I use Simply Silica. Because Simply Silica is a concentrate, I find it very cost-effective.

    The fertilizer does have to be mixed and needs to be applied every two weeks. Since it doesn’t contain any nitrogen or phosphorus, I only use it after the fruit is set. I use it in addition to Neptune’s Harvest because my pumpkin vines still need some nitrogen and phosphorous to grow well even after the pumpkin starts growing. To use, I simply add one teaspoon of Simply Silica to a gallon of water and use it in place of water once every two weeks. Be aware that using too much concentrate in the water or applying the solution too often can cause the pumpkins to split, explode, or fall off the vine before they are ripe.

    Pros:

    • The bottle makes 47 gallons
    • Easy application
    • Supplements the potassium in the soil
    • Water soluble

    Cons:

    • Has to be mixed
    • Doesn’t have nitrogen or phosphorus
    • Needs to be applied every 2 weeks

    Best Granule Fertilizer for Pumpkins 

    Granules have a larger grain size than powder and dissolve more readily. Some granules are coated, so they release nutrients over time instead of all at once.  

    5. Espoma Blood Meal Granules Organic Plant Food 

    Espoma Blood Meal Granules Organic Plant Food

    Blood meal is the best source of nitrogen I have found. I like Espoma Blood Meal because the company has a range of good products for the pumpkin patch and is reputable. Blood meal is a by-product of the cattle industry, so I like using something that would otherwise go to waste. In addition, Espoma Blood Meal is organic, and I try to use organic products in my vegetable garden.

    Blood meal can burn your pumpkin plants if you apply too much. Vines can also produce lots of foliage and no pumpkins if they have too much nitrogen. Follow the label directions as to how much to put out per square foot. Blood meal is also a bit messy, so stand upwind when applying the blood meal to your pumpkin vines. Just like blood, blood meal will stain your clothes if you get it on you. Espoma, as well as other manufacturers, suggests you use waterproof gloves when applying the blood meal. To use, I sprinkle the blood meal beside the entire length of the vine and water it in good. Do not get the blood meal on the vine, or it can burn the leaves and stem.

    Pros:

    • Produces deep green leaves and healthy vines
    • Concentrated source of nitrogen
    • Organic

    Cons:

    • Uses more water than other forms of fertilizer
    • Can burn plants if an excess is applied
    • Messy, stand upwind, or you get it on you
    • Wear waterproof gloves when handling

    6. Burpee Bone Meal Fertilizer 

    Burpee Bone Meal Fertilizer

    Burpee Bone Meal Fertilizer is a great source of phosphorous and also has some nitrogen in it. I use it when I want the pumpkin vines to bloom and set fruit. Like blood meal, bone meal is a by-product of the cattle industry, so I am using something that would otherwise go to waste. Vegans and vegetarians may not want to use this product, though.

    Burpee Bone Meal Fertilizer breaks down slowly, so you do not have to use it as often as a liquid fertilizer.  Burpee Bone Meal contains both nitrogen and phosphorous but won’t cause excessive growth if you follow the label directions. It is organic, which is a plus to me.

    However, Burpee Bone Meal does not contain any potassium, so it shouldn’t be used after the pumpkin vines set fruit. It is also messy, so stand upwind when applying and wear waterproof gloves. I find the grit unpleasant if it gets on me. I spread it beside the vines once every four weeks and water it in well. Don’t spread it directly on the vines, or it can burn the leaves.

    Pros:

    • Releases nutrients slowly
    • Organic
    • Contains nitrogen and phosphorous

    Cons:

    • Messy, stand upwind when applying
    • Wear waterproof gloves when handling
    • Does not contain potassium

    7. Lilly Miller Morcrop Tomato & Vegetable Food 

    Lilly Miller Morcrop Tomato & Vegetable Food 5-10-10

    Lilly Miller Morcrop Tomato & Vegetable Food has enough nitrogen to keep your plant healthy but does not cause the vines and foliage to grow instead of the pumpkins. Lilly Miller Morcrop Tomato & Vegetable Food is high in phosphorous and potassium. I use it to support fruit set and the growth of the pumpkin. It helps the stem and rind on the pumpkin grow and makes them sturdy enough to support the insides of the pumpkin. Without enough potassium, the rind will be too soft.

    This fertilizer breaks down slowly, so you can save money by using it less often. You only have to use it every four weeks as opposed to a liquid, which has to be used every two weeks. Morcrop Tomato & Vegetable Food is easy to use and doesn’t have much of an odor. It has all three macronutrients your pumpkin vine needs in it. Too much of it can cause your pumpkins to split or explode. This product is natural but not organic. To use, I spread it along the pumpkin vine, and then I water the area.

    Pros:

    • Good source of nitrogen, phosphorous, and potassium
    • Easy to use
    • Slow release
    • Low odor

    Cons:

    • Too much can cause your pumpkins to split
    • Natural but not organic
    • Wear waterproof gloves when handling
    •  Needs to be reapplied every 4 weeks

    8. Espoma Organic Garden-Tone  – Best All Around Fertilizer for Pumpkins

    Espoma Organic Garden-Tone 3-4-4 Organic Fertilizer

    If you just want one fertilizer for your pumpkins, buy Espoma Organic Garden-Tone. Espoma has a solid reputation for great products. I use this on all my other vegetables as well as my squash and pumpkins. It has enough nitrogen, phosphorous, and potassium for all stages of growth. Espoma Organic Garden-Tone also has many micronutrients. In addition, it has six kinds of probiotics and has Biotone, which Espoma developed and says feeds the soil microbes.

    Because Espoma Organic Garden-Tone is slow-release, you only have to spread it once every four weeks. I think it smells bad, but not so bad I get sick to my stomach when I use it. I just prefer to stay upwind when I spread it and wear gloves when handling it. I spread this fertilizer beside the pumpkin vines or whatever vegetable I am fertilizing and then water the area well. Without water, the fertilizer won’t reach your pumpkin’s roots where it needs to go for the pumpkin to use it.

    Pros:

    • Inexpensive
    • Slow-release
    • Good source of macro and micronutrients
    • Low salt content
    • It can be used on other vegetables
    • Organic

    Cons:

    • Smells bad
    • Use gloves when handling
    •  Needs to be applied every 4 weeks

    9. Miracle-Gro Performance Organics Edibles Plant Nutrition Granules – Best Budget Fertilizer for Pumpkins 

    Miracle-Gro Performance Organics Edibles Plant Nutrition Granules - Plant Food

    Some pumpkin fertilizers can be expensive. If you are on a tight budget, you may not be able to afford them. Don’t worry; you can still get a fertilizer that will help you get great pumpkins. 

    My favorite budget-friendly fertilizer to use is Miracle-Gro Performance Organics Edibles Plant Nutrition Granules. Miracle-Gro is a respected company, and they are switching from producing inorganic products to organic products. There is nothing wrong with synthetic fertilizers, but I prefer organic products when they are available, especially when I am growing something I intend to eat, like pie pumpkins.

    This fertilizer is easy to apply, and I don’t have to worry about getting it on me. Miracle-Gro Performance Organics Edibles Plant Nutrition Granules are good for all stages of the pumpkin vine’s life, so they are the only fertilizer you need to buy if you don’t have the money for several more specialized fertilizers. The fertilizer can cause a crust on the soil if you don’t use enough water to water it in well. This fertilizer does use more water than liquid fertilizers. Unless it is watered in well, the fertilizer is not available for the roots to absorb.

    To use, I just sprinkle Miracle-Gro Performance Organics Edibles Plant Nutrition Granules beside the entire length of the vine once every four weeks and water it in well.

    Pros:

    • Easy to apply 
    • Organic
    • Budget Friendly
    • Good for edible pumpkins
    • Balanced for all stages of the vine’s life

    Cons:

    • Can crust on the soil
    • Needs to be applied every 4 weeks

    Final Thoughts

    The best fertilizer for your pumpkins depends on the type of fertilizer and the growth stage of the pumpkin. Pumpkins need a high nitrogen fertilizer when growing vines, a high phosphorous fertilizer when blooming and setting fruit, and a high potassium fertilizer while the pumpkin grows. All of the fertilizers listed in this article are high-quality fertilizers that will help you grow great pumpkins.

    Photo of author

    Stephanie Suesan Smith

    Stephanie Suesan Smith has a Ph.D. in psychology that she mainly uses to train her dog. She has been a freelance writer since 1991. She has been writing for the web since 2010. Dr. Smith has been a master gardener since 2001 and writes extensively on gardening. She has advanced training in vegetables and entomology but learned to garden from her father. You can see her writing samples at https://gardencopywriter.com/garden-writing, and her vegetable blog at https://stephaniesuesansmith.com/.

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