Guatemalan Blue Squash

Guatemalan Blue Squash, scientifically known as Cucurbita moschata, is a unique and delicious winter squash variety. This heirloom cultivar is valued for its sweet, nutty flavour, vibrant blue-grey skin, and impressive size. It is an excellent addition to any home garden, providing nutritious food and visual appeal. In this article, we will discuss the entire process of planting, growing, harvesting, and storing Guatemalan Blue Squash.

Days to Grow95-110 days
Square Foot Garden Spacing1 plant per 16 square feet (4×4 ft spacing)
Gardening EffortModerate
When to Plant4-6 weeks before the last frost date
Yield1-2 fruits per plant
Frost ToleranceNot frost-tolerant; protect from frost
Hours of Light Needed6-8 hours of direct sunlight daily
Soil ConditionsWell-draining, fertile soil with pH 6.0-6.8
Days to Maturity95-110 days from planting

Gardening Shortcut Links

Square Foot Gardening Section

Preparing the Soil for Guatemalan Blue Squash

To ensure a successful crop of Guatemalan Blue Squash, start by preparing the soil in the following way:

  1. Choose a location: Select a location with full sun exposure and well-draining soil. Guatemalan Blue Squash plants are large and need plenty of space to grow; provide at least 4 feet between plants.
  2. Test and amend the soil: The ideal soil pH for Guatemalan Blue Squash is between 6.0 and 6.8. Perform a soil test to determine the current pH and amend as needed with lime or sulfur to reach the desired level. Additionally, incorporate organic matter like compost or well-rotted manure to improve soil fertility and structure.
  3. Prepare planting mounds: Create mounds of soil approximately 12 inches in diameter and 6 inches high, spaced 4 feet apart. This raised planting technique allows for better drainage and warmer soil, which Guatemalan Blue Squash prefers.

Planting Guatemalan Blue Squash Seeds

Follow these steps to plant Guatemalan Blue Squash seeds successfully:

  1. Sow seeds: Plant indoors 4-6 weeks before the last frost date. 
  2. Wait for the right temperature: TransPlant Guatemalan Blue Squash seeds when soil temperatures reach at least 60°F. Depending on your location, this typically occurs in late spring or early summer.
  3. Water consistently: Water the seeds gently but thoroughly, ensuring that the soil remains consistently moist during germination.

Caring for Guatemalan Blue Squash Plants

Proper care is essential for a healthy and productive Guatemalan Blue Squash crop:

  1. Thin seedlings: When seedlings reach 3-4 inches in height, thin them to leave only the two most vigorous plants. This will prevent overcrowding and promote better growth.
  2. Mulch: Apply a 2-3 inch layer of organic mulch, such as straw or wood chips, around the base of the plants. Mulch helps retain soil moisture, suppress weeds, and regulate soil temperature.
  3. Fertilize: Apply a balanced, all-purpose fertilizer according to the package instructions, typically every 4-6 weeks. This will provide the necessary nutrients for vigorous growth and fruit production.
  4. Water deeply: Water Guatemalan Blue Squash plants deeply and consistently, providing approximately 1-1.5 inches of water per week. Avoid overhead watering to minimize the risk of foliar diseases.
  5. Monitor for pests and diseases: Keep an eye out for common squash pests, such as squash bugs and cucumber beetles, and treat them as needed with organic or chemical controls. Practice good garden hygiene, such as removing plant debris, to reduce the risk of diseases like powdery mildew and squash vine borers.

Harvesting Guatemalan Blue Squash

Follow these guidelines to harvest Guatemalan Blue Squash at the perfect time:

  1. Check for maturity: Guatemalan Blue Squash typically takes 95-110 days to reach maturity. Look for a hard, blue-grey rind that is difficult to pierce with a fingernail. The skin should be matte, not shiny. Additionally, the stem should be dry and brown.
  2. Test for ripeness: Gently press your thumbnail into the squash’s skin. If it resists puncture, the squash is ripe and ready to harvest.
  3. Cut, don’t pull: Use a sharp, clean pair of pruning shears or a knife to cut the squash from the vine. Leave a 2-3 inch stem attached to prevent rot and extend storage life.
  4. Handle with care: Guatemalan Blue Squash can be pretty heavy, so handle them carefully to avoid injury. Additionally, be cautious not to damage the skin, as this can shorten storage life.

Storing Guatemalan Blue Squash

Proper storage is essential to enjoy your Guatemalan Blue Squash harvest for months to come:

  1. Cure the squash: Before storing, cure Guatemalan Blue Squash by placing them in a warm, well-ventilated area for 10-14 days. This process allows the skin to harden further, enhancing storage life.
  2. Choose a suitable storage area: Store cured squash in a cool, dark, and well-ventilated area, such as a basement or garage. Ideal storage temperatures range between 50-60°F with 50-70% relative humidity.
  3. Inspect regularly: Check stored squash regularly for signs of rot or spoilage. Promptly remove any compromised squash to prevent the spread of decay to other fruits.
  4. Store individually: Avoid stacking or crowding squash, as this can promote the spread of decay. Instead, store them individually on shelves or in crates with adequate airflow.


Growing Guatemalan Blue Squash can be a rewarding and delicious endeavour for any gardener. By following the steps outlined in this article – from preparing the soil and planting seeds to caring for plants and harvesting ripe fruits – you’ll be well on your way to enjoying a bountiful harvest of this unique and flavorful winter squash variety. In addition, proper storage techniques will ensure that you can savour the taste of Guatemalan Blue Squash long after the growing season has ended.

Seeds and planting
Links and Resources

Recommended Products
(These are some of what I use)

These nursery bags
These Grow bags

Pages Seeds Page
Get a Head Start on Spring: The Benefits of Starting Your Seeds Indoors
Saving Vegetable Seeds: A Comprehensive Guide to Gardening Success Planting Guide
Pollock Tomatoes (North hardy Tomato variety)
Tomatoes (Useful information on starting tomatoes from seed)

DIY Garden Irrigation System: A Detailed Guide for Northwest Ontario

Blog Posts

When to start planting seeds
Germination testing your seeds
Looking for sources for seeds?
Heirloom seeds
Chitting your way to more potatoes
So it's before the first frost; what can I plant?


Individual seed and plant information is available in the  "Gardening Shortcut Links" above under "North Hardy Plants to grow". I have successfully grown all of these, and most I grow year to year.






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