Pumpkin Fertilizer Requirements: Guide To Feeding Pumpkin Plants

Small Pumpkin Plant
pumpkin fertilizer
(Image credit: StudioBarcelona)

Whether you’re after the great pumpkin that will win first prize at the fair, or lots of smaller ones for pies and decorations, growing the perfect pumpkin is an art form. You spend all summer tending your vine, and you want to get the most out of it that you can. Fertilizing pumpkins is essential, as they will devour nutrients and run with them. Keep reading to learn more about pumpkin fertilizer requirements.

Fertilizer for Pumpkins

Pumpkins are heavy feeders and will eat up whatever you give them. Different nutrients promote different kinds of growth, however, so when fertilizing pumpkins, it’s important to pay attention to what stage of growth your pumpkin is in and feed it accordingly. Commercial fertilizers come with three numbers on their packaging. These numbers represent nitrogen, phosphorus, and potassium, always in that order. When feeding pumpkin plants, apply three successive fertilizers, each heavy in one of those numbers, in that same order. Nitrogen promotes green growth, making for plenty of vines and leaves. Apply a weekly nitrogen-heavy fertilizer early in the growing season to produce a healthy plant. Once the flowers start to form, switch to a phosphorus-heavy fertilizer for plentiful blossoms. When the actual pumpkins appear, use a potassium-rich fertilizer for healthy fruit.

Feeding Pumpkin Plants

Fertilizer is important, but sometimes a little can go a long way. Nitrogen promotes growth, but if you add too much, you risk burning your leaves or reducing flower growth. Similarly, too much potassium can sometimes encourage pumpkins to grow faster than they’re meant to and cause them to explode right out of their skins! Apply your fertilizer in moderation and wait to see what results a little gets you before adding a lot. If you’re new to growing pumpkins, a very basic and balanced 5-10-5 fertilizer applied moderately all through the growing season is much less intensive and should still yield good results.

Liz Baessler
Senior Editor

The only child of a horticulturist and an English teacher, Liz Baessler was destined to become a gardening editor. She has been with Gardening Know how since 2015, and a Senior Editor since 2020. She holds a BA in English from Brandeis University and an MA in English from the University of Geneva, Switzerland. After years of gardening in containers and community garden plots, she finally has a backyard of her own, which she is systematically filling with vegetables and flowers.