How to Choose the Right Types of Pumpkins to GrowThe first step to ensure gardening success? If it’s still below 32 degrees outside, even just at night, it’s not the right time to plant your pumpkins. Take out the guesswork by plugging your zip code into the Farmer's Almanac planting calendar tool to determine the ideal time to sow your pumpkin seeds outdoors. “Drip irrigation systems really help with this.”HIRALIY 50ft Drip Irrigation Kit Plant Watering System $21 at AmazonCreate the right soil environment. “I recommend either commercial 8-8-8 fertilizer or organic plant-tone fertilizer,” he says; these specific fertilizer products can help your pumpkins grow their very best.