Upper Ground Sweet Potato Squash Seeds, Rare 1790 Heirloom

Upper Ground Sweet Potato Squash is the rarest seed we have ever carried, and the oldest story in our catalog. Thomas Jefferson documented this variety in 1790, calling it a potatoe-pumpkin when he mailed seeds to a friend. More than two centuries later it is still grown in the gardens at Monticello, and almost nowhere else. It earned its keep the hard way: an Appalachian Kentucky heirloom bred for hot, dry summers and thin patience.

Why this squash

• Vine borer resistant: a true Cucurbita moschata, with the dense stems that squash vine borers rarely defeat
• Drought and heat tolerant: bred in the South for exactly the weather a Kansas July delivers
• Sweet potato flesh: tan skin over dense orange flesh that cooks like its namesake, fruits can reach 20 pounds
• Keeps for months: like our other moschata varieties, cured fruits store 4 to 6 months in a cool, dry spot at 50 to 60 F
• Open-pollinated: save seed from your best fruit and it grows true next year

About 110 days to maturity. Plan for long, vigorous vines and give it room to run.

A small first batch

This is a limited first release: 10 packets of 10 seeds, and when they are gone they are gone until we grow our own seed crop. If you collect rare heirlooms or you have been fighting vine borers for years, this is the packet to grab.

New to this variety? Read our complete Upper Ground Sweet Potato growing guide for Zone 6b planting dates, spacing, and harvest.

✅ Germination Promise: if your seeds fail to germinate under proper growing conditions, contact us within one year and we will replace them or refund you.

Grows well with

Pair it with our other vine borer resistant moschata heirlooms: Seminole Pumpkin for the ancient survivor, or Dickinson Pumpkin for the pie chapter. Browse the full Vine Borer Resistant collection.