When to Plant Broccoli in Butte

Can Broccoli Mature in Butte?

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.

From the usual planting window, Butte typically provides about 1877 growing degree days for broccoli. With a typical crop target of 900, that leaves a heat margin of +977. 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.

How Different Broccoli Varieties Affect Results

The season in Butte 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

Main risk: When this crop underperforms in Butte, the culprit is usually timing or variety choice rather than the climate itself.

How Frost Affects Planting Dates for Broccoli in Butte

Butte usually has about 84 frost-free days, with a typical last spring frost around June 13 and a typical first fall frost around September 5.

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 Butte, the culprit is usually timing or variety choice rather than the climate itself.

In Butte, the local season usually gives broccoli plenty of breathing room when planting happens around June 6. 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.