Practical planning tools for short growing seasons.
Climate-based broccoli planting guide for Durango, Colorado
When to Plant Broccoli in Durango
Broccoli is usually a good match for the season in Durango. Gardeners generally have enough margin to think about preference and quality, not just speed.
Typical Planting Window
Strong fit in this climate
Use the planting dates below for broccoli in Durango.
Start indoors
April 9
Typical planting windowMay 14 – May 28
MethodTransplant
Typical days to maturity60–75
Broccoli is usually started indoors around April 9 and planted outdoors during the normal local window of May 14 to May 28.
Most varieties need about 60–75 days to reach maturity once they are in the garden.
Broccoli is usually a dependable choice in Durango. The season is supportive enough that gardeners usually have options instead of feeling pushed into only the quickest path.
This crop is usually dependable here, though the difference between decent and excellent results still comes from steady growth and harvest stage.
Best local strategy:
Treat the season as supportive, then focus on consistency and crop quality more than simple maturity insurance.
Can Broccoli Mature in Durango?
Growing degree days measure how much useful warmth typically accumulates during the season. For broccoli, this helps estimate whether local heat accumulation is usually enough for the crop to reach maturity on time.
Available GDD (base 40)1555
Typical crop GDD target900
Heat margin+655
From the usual planting window, Durango typically provides about 1555 growing degree days for broccoli. With a typical crop target of 900, that leaves a heat margin of +655. That heat margin usually gives the crop a dependable buffer, so gardeners have some flexibility in planting date and variety choice without pushing the crop close to the edge.
When Is It Too Late to Plant?
If planting later than usual, this table shows how much growing degree day heat is still available from each point in the season. It is most useful for judging how much flexibility you still have before the crop starts losing margin.
Checkpoint
Remaining GDD
Heat margin
Fit vs typical target
Apr 15
1591
+691
Comfortable
May 15
1587
+687
Comfortable
Jun 1
1518
+618
Comfortable
Jun 15
1400
+500
Comfortable
Jul 1
1203
+303
Comfortable
How Different Broccoli Varieties Affect Results
The season in Durango usually supports most broccoli varieties comfortably, which means the more useful decision is what kind of crop you want rather than simply how fast it finishes.
Varieties that often fit well here include:
De Cicco
— an early broccoli often chosen where gardeners want flexibility and quicker harvest
Packman
— a dependable standard with good short-season practicality
Green Magic
— a strong early hybrid that often handles the main spring window well
Belstar
— productive and reliable where the season gives a reasonable cool-weather runway
Marathon
— more exposed if spring is delayed or summer heat arrives early
Best Broccoli Varieties for Durango
Broccoli variety choice in Durango is mostly about head reliability, side-shoot production, stress tolerance, and how cleanly the crop fits the cool part of the season.
May 28
local season starts
September 30
frost pressure returns
Less heat used1555 GDD available
Hover or tap the dots to see which recommended varieties use that much local heat.
For Durango, start with Packman and Green Magic for broccoli when you want dependable early broccoli heads or strong early hybrid broccoli.
Choose De Cicco when you want flexible early broccoli and side shoots.
Look at Marathon and Belstar when you specifically want later broccoli plantings or reliable main-season broccoli.
Compare each variety’s heat need and maturity timing against the local frost-free window before choosing what to grow.
Recommended starting point
PackmanEarly
850 GDD needed1555 available before frost
May 28September 30
Comfortable fit
Why this fit?
Local season fit:
Packman leaves about 705 GDD cushion against the normal Durango crop heat estimate.
Best for: dependable early heads.
A practical early broccoli with good short-season usefulness.
Tradeoff: Practical more than specialty.
Green MagicEarly
850 GDD needed1555 available before frost
May 28September 30
Comfortable fit
Why this fit?
Local season fit:
Green Magic leaves about 705 GDD cushion against the normal Durango crop heat estimate.
Best for: strong early hybrids.
A strong early hybrid that often handles the main spring broccoli window well.
Tradeoff: Still needs cool growing conditions to finish well.
Fastest / most cushion
De CiccoVery early
750 GDD needed1555 available before frost
May 28September 30
Comfortable fit
Why this fit?
Local season fit:
De Cicco leaves about 805 GDD cushion against the normal Durango crop heat estimate.
Best for: flexible early broccoli.
An early broccoli that is useful when gardeners want flexibility, side shoots, and a quicker harvest path.
Tradeoff: Heads may be less uniform than hybrid types.
Also realistic
MarathonLate
1050 GDD needed1555 available before frost
May 28September 30
Comfortable fit
Why this fit?
Local season fit:
Marathon leaves about 505 GDD cushion against the normal Durango crop heat estimate.
Best for: later broccoli plantings.
A slower broccoli that is more exposed if spring is delayed or summer heat arrives early.
Tradeoff: More exposed if spring is delayed or summer heat arrives early.
BelstarMid-season
950 GDD needed1555 available before frost
May 28September 30
Comfortable fit
Why this fit?
Local season fit:
Belstar leaves about 605 GDD cushion against the normal Durango crop heat estimate.
Best for: reliable main-season broccoli.
A productive broccoli that works well where the season gives a reasonable cool-weather runway.
Tradeoff: Needs more cool-season runway than early broccoli.
GDD comparisons are a planning shortcut, not a guarantee. Soil, watering, sowing depth, pests, transplant quality, and harvest goals still affect the final result.
Variety class
Typical days to maturity
Typical GDD need
Local fit
Very early
55–60
750
Good fit
Early
60–68
850
Good fit
Mid-season
68–78
950
Good fit
Late
78–90
1050
Good fit
Main risk: When this crop underperforms in Durango, the culprit is usually timing or variety choice rather than the climate itself.
How Frost Affects Planting Dates for Broccoli in Durango
Durango usually has about 125 frost-free days, with a typical last spring frost around May 28 and a typical first fall frost around September 30.
Typical last spring frostMay 28
Typical first fall frostSeptember 30
Typical frost-free days125
Minimum safe temperature28°F /
-2
°C
Broccoli is generally
lightly frost tolerant
and temperatures below about 28°F (
-2
°C) can slow growth or damage plants.
Broccoli is usually tolerant enough of cool conditions that light frost is not the main concern. The more useful question is how early planting affects establishment and overall crop quality.
When this crop underperforms in Durango, the culprit is usually timing or variety choice rather than the climate itself.
In Durango, the local season usually gives broccoli plenty of breathing room when planting happens around May 21. For a better local margin, gardeners usually do best in south-facing walls, sheltered gardens, raised beds, and sunnier urban lots. Cooler spots like low spots, exposed sites, and shadier yards often make timing tighter. For broccoli, the best local sites often help the crop get moving earlier and make timing a little more forgiving.
Set up broccoli for steady growth and pest protection
The better results usually come from steady growth, pest protection, and avoiding early setbacks.
Transplant support
Strong young plants help avoid slow starts and uneven sizing.