When to Plant Blueberries in St. Mary's County, MD
Blueberries are long-lived shrubs producing sweet, antioxidant-rich berries. They require acidic soil and are attractive ornamental plants with fall color and spring flowers.
St. Mary's County, Maryland is in USDA Zone 7a. The average last spring frost is April 5 and the first fall frost is November 4, giving you a growing season of approximately 213 days.
At an elevation of 156 feet, St. Mary's County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Blueberries during the growing season.
St. Mary's County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.9
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Blueberries Planting Timeline — St. Mary's County, MD
Blueberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 26 | Apr 26 – May 10 |
· 48" apart · Rows 72" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
730–1095 days
Soil pH
4.5 – 5.5
USDA Zone
Zone 7a
Growing Season
213 days
Growing Tips for St. Mary's County
Plant at least two varieties for cross-pollination. Acidify soil with sulfur or pine needle mulch to maintain pH 4.5-5.5. Protect ripening berries from birds with netting.
Companion Planting
Good Companions
Level Up Your Garden
Blueberries in Other Locations
Frequently Asked Questions
When should I plant Blueberries in St. Mary's County, MD?
St. Mary's County is in Zone 7a with an average last frost of April 5. Plan your Blueberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Mary's County, MD?
St. Mary's County, Maryland is in USDA Hardiness Zone 7a. The average last spring frost is April 5 and first fall frost is November 4.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help St. Mary's County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.