Metro areas

Gardening in Provo-Orem-Lehi, UT

This metro spans USDA zones 6a to 7a, so there is no single zone for Provo-Orem-Lehi, UT and anyone who gives you one is rounding. 48% of its ZIP codes are zone 7a; the rest are not.

USDA zones 6a–7a 3 zones across 27 ZIP codes
ZIP codes 27 27 have a NOAA station within range
Weather stations 13 NOAA 1991–2020 normals, across 5,396 sq mi

Which zone you are in depends where you are

Provo-Orem-Lehi, UT covers 3 hardiness zones. A guide that gives the metro one zone has picked whichever is largest and rounded everyone else into it — which is fine for the 48% in zone 7a and wrong for the other 52%. Here is the actual split.

Zone ZIP codes Share  
7a 13 48%
6b 9 33%
6a 5 19%

Zones are published per ZIP code, so yours is exact even though the metro's is not. The hardiness tool will tell you which one you are in.

Your freeze dates

Last spring freeze April 17 – June 2
First fall freeze September 16 – October 25

Those are the earliest and latest medians among the 13 stations serving this metro — not an average, and not one station standing in for the rest. Half of years freeze later than a station's own median.

The spread is the point. Even in a metro that is one hardiness zone throughout, its stations disagree about the last spring freeze. Hardiness zone and frost date measure different things — a zone is the average annual coldest night, a freeze date is when the season turns — and a place can be uniform in one and varied in the other. Use the tools below with your own ZIP rather than the ends of this range.

Your growing season

NOAA publishes a growing-season length for each station, and across the 13 stations serving Provo-Orem-Lehi, UT it runs 103–188 days . That figure is published, not computed from the two freeze dates — subtracting one from the other gives the wrong answer wherever a season crosses New Year. Mean summer high (June–August) runs 78–92 °F , at or above the 90 °F point where cool-season crops bolt and tomato and pepper pollen fails — so midsummer sowings of lettuce and its relatives are worth holding here.

When to start seeds in Provo-Orem-Lehi, UT

Every spring job for 63 crop dates, counted from this metro's own last spring freeze. Each is a range across all 13 stations — the earliest and latest that job falls anywhere in the metro — because no one station speaks for the whole area.

Crop Job When Offset
Green Onions Start indoors February 20 – April 7 8 weeks before
Peppers Start indoors February 20 – April 7 8 weeks before
Broccoli Start indoors March 6 – April 21 6 weeks before
Cabbage Start indoors March 6 – April 21 6 weeks before
Collards Start indoors March 6 – April 21 6 weeks before
Kale Start indoors March 6 – April 21 6 weeks before
Leaf Lettuce Start indoors March 6 – April 21 6 weeks before
Peas Direct sow March 6 – April 21 6 weeks before
Spinach Direct sow March 6 – April 21 6 weeks before
Sweet Potato Start indoors March 6 – April 21 6 weeks before
Tomatoes Start indoors March 6 – April 21 6 weeks before
Bok Choy Start indoors March 13 – April 28 5 weeks before
Kohlrabi Start indoors March 13 – April 28 5 weeks before
Swiss Chard Start indoors March 13 – April 28 5 weeks before
Arugula Direct sow March 20 – May 5 4 weeks before
Baby Salad Greens Direct sow March 20 – May 5 4 weeks before
Beets Direct sow March 20 – May 5 4 weeks before
Green Onions Direct sow March 20 – May 5 4 weeks before
Mustard Greens Direct sow March 20 – May 5 4 weeks before
Okra Start indoors March 20 – May 5 4 weeks before
Radishes Direct sow March 20 – May 5 4 weeks before
Turnips Direct sow March 20 – May 5 4 weeks before
Cabbage Set out March 27 – May 12 3 weeks before
Carrots Direct sow March 27 – May 12 3 weeks before
Collards Direct sow March 27 – May 12 3 weeks before
Collards Set out March 27 – May 12 3 weeks before
Cucumbers Start indoors March 27 – May 12 3 weeks before
Green Onions Set out March 27 – May 12 3 weeks before
Kale Direct sow March 27 – May 12 3 weeks before
Kale Set out March 27 – May 12 3 weeks before
Kohlrabi Direct sow March 27 – May 12 3 weeks before
Kohlrabi Set out March 27 – May 12 3 weeks before
Leaf Lettuce Direct sow March 27 – May 12 3 weeks before
Pumpkins Start indoors March 27 – May 12 3 weeks before
Summer Squash Start indoors March 27 – May 12 3 weeks before
Winter Squash Start indoors March 27 – May 12 3 weeks before
Zucchini Start indoors March 27 – May 12 3 weeks before
Bok Choy Direct sow April 3 – May 19 2 weeks before
Bok Choy Set out April 3 – May 19 2 weeks before
Broccoli Set out April 3 – May 19 2 weeks before
Cilantro Direct sow April 3 – May 19 2 weeks before
Leaf Lettuce Set out April 3 – May 19 2 weeks before
Swiss Chard Direct sow April 3 – May 19 2 weeks before
Swiss Chard Set out April 3 – May 19 2 weeks before
Dill Direct sow April 10 – May 26 1 week before
Bush Beans Direct sow April 24 – June 9 1 week after
Cucumbers Set out April 24 – June 9 1 week after
Pumpkins Direct sow April 24 – June 9 1 week after
Pumpkins Set out April 24 – June 9 1 week after
Summer Squash Direct sow April 24 – June 9 1 week after
Summer Squash Set out April 24 – June 9 1 week after
Sweet Corn Direct sow April 24 – June 9 1 week after
Tomatoes Set out April 24 – June 9 1 week after
Winter Squash Direct sow April 24 – June 9 1 week after
Winter Squash Set out April 24 – June 9 1 week after
Zucchini Direct sow April 24 – June 9 1 week after
Zucchini Set out April 24 – June 9 1 week after
Cucumbers Direct sow May 1 – June 16 2 weeks after
Okra Direct sow May 1 – June 16 2 weeks after
Okra Set out May 1 – June 16 2 weeks after
Peppers Set out May 1 – June 16 2 weeks after
Southern Peas Direct sow May 1 – June 16 2 weeks after
Sweet Potato Set out May 1 – June 16 2 weeks after

The week offsets are conventional extension guidance and vary by variety; the freeze dates they are counted from are measured. For a single date rather than a range, run when do I start my seeds? with your own ZIP code.

What survives the winter changes across Provo-Orem-Lehi, UT

Of 74 perennial fruits, nuts, berries, vegetables and herbs, 58 come through the winter in zone 7a and only 51 in zone 6a. That is a different garden at each end of the same metro.

Zone ZIPs Survive Fail for being too warm
6a 5 51 of 74 0
6b 9 51 of 74 0
7a 13 58 of 74 1

The last column is the counterintuitive one, and it is why the totals do not simply rise as the winters get milder. Most temperate fruit needs a documented number of hours below about 45 °F to break dormancy and set a crop, so an apple fails in a winter that is too warm; currants and rhubarb cook in the summer heat that comes with it. See the full list with reasons.

The 13 stations behind these numbers

Every figure above comes from these, and each is named so you can check it. Distances vary by ZIP code, so the tools report yours rather than this page guessing.

Station NOAA ID Last spring freeze First fall freeze Season
Alpine, UT USC00420061 May 3 October 12 159 days
Fairfield, UT USC00422696 June 2 September 16 103 days
Levan, UT USC00425065 May 10 October 7 148 days
Little Sahara Rec Area, UT USC00425138 May 15 October 1 137 days
Nephi, UT USC00426135 May 6 October 10 156 days
Orem Trtmt Plt, UT USC00426538 April 19 October 19 182 days
Pleasant Grove, UT USC00426919 April 17 October 25 188 days
Provo Byu, UT USC00427064 April 18 October 21 185 days
Santaquin Chlorinator, UT USC00427686 May 4 October 11 157 days
Spanish Fk Pwr House, UT USC00428119 April 25 October 18 174 days
Sundance, UT USC00428465 May 17 October 5 138 days
Timpanogos Cave, UT USC00428733 May 2 October 16 161 days
Utah Lake Lehi, UT USC00428973 April 30 October 9 159 days

These are medians, not averages — NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.

Work out your own dates

Each of these takes a ZIP code and answers for that ZIP alone, citing the station it used and how far away it is. There is a ZIP box in the header of every page.

Where these numbers come from

The hardiness zone is the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. The freeze dates are NOAA's 1991–2020 Climate Normals, read from every station whose normals cover a ZIP code in this metro. Nothing here is estimated, and no station stands in for another.

This page names no single station on purpose. Picking one to represent a metro sounds reasonable and is not: the station serving the most ZIP codes is an artifact of where ZIP centroids happen to fall, and it selects a lock on the Monongahela for Pittsburgh and a far southern suburb for Chicago. A range across every station is true; a single cited date for a whole metro is not.

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