You can fix this by mixing in sand or compost to loosen things up. · when sprouts emerge too close, they intensely compete for space, vital nutrients, and precious water. If you want those long, sweet, crunchy carrots you see in garden catalogs, this guide will help you get there. · heat stress, lack of water or nutrients, and overcrowding cause thin carrots. One of the most common causes of thin carrots is overcrowding. If your soil is full of clay or too tightly packed, the roots will struggle to grow long and deep, often resulting in short, stubby carrots. · so today, i’m sharing my complete guide to why your carrots might be small — plus the exact steps you can take to fix it. Such fierce, unrelenting rivalry chokes their growth, making them twist around each other or stay small and pathetic. Carrots are prone to this due to how small their seeds are, which makes it difficult to space them out properly when seeding. Carrots need loose, crumbly soil to support their long root growth. · here are the 7 most common reasons for small carrots and what to do about them: Heavy clay or compacted soils make it difficult for the carrots to push through and expand. Weed, water, and fertilize regularly, and harvest when carrots are ¾ inch in diameter. · carrots like loose, sandy, well-drained soil that lets their roots stretch straight down. Rocky, compacted soil. For larger carrots, plant them in the spring or fall in full sun and rich soil with proper spacing.