Glendale, Arizona planting calendar and frost dates
Glendale is in USDA hardiness zone 9b. The last spring frost typically comes around January 20 and the first fall frost around December 15, giving about 331 frost-free days a year.
- Typical last frost
- January 20
- Typical first frost
- December 15
- Frost-free season
- 331 days
Frost dates in Glendale
Last spring frost
- December 23Risky: frost later than this in 9 years out of 10
- January 20Typical: a later frost in half of years
- February 18Safe: a later frost only 1 year in 10
First fall frost
- November 28Risky: frost earlier than this 1 year in 10
- December 15Typical: an earlier frost in half of years
- New yearLate: in about 1 year in 10, the first frost waits until after December 31
The growing season between the typical last and first frosts is about 331 days. Frost here means a low of 32°F at the weather station. A hard freeze (28°F), which damages most hardy crops too, typically ends around January 3 and returns around December 29.
NOAA U.S. Climate Normals 1991-2020 for Youngtown, 7.7 miles WNW of the city center. Low-lying and rural spots often frost later in spring and earlier in fall than airports and city centers.
What to plant each month in Glendale
January
Start indoors: basil, cantaloupes, celery, eggplants, peppers, ranunculus, tomatoes, watermelons
Plant or sow outdoors: asparagus, avocados, beets, black-eyed susans, blackberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, dahlias, dill, figs, garden mums, gladioli, grapes, green onions, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, onions, oregano, parsley, petunias, potatoes, radishes, ranunculus, rosemary, roses, sage, snapdragons, spinach, sunflowers, sweet corn, swiss chard, thyme, turnips
February
Start indoors: cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, zucchini
Plant or sow outdoors: avocados, garden mums, ginger, grapes, green onions, lavenders, lilies, marigolds, mints, nasturtiums, oregano, parsley, petunias, rosemary, sage, st. augustinegrass, sunflowers, sweet corn, thyme
March
Start indoors: zinnias
Plant or sow outdoors: basil, bermudagrass, cantaloupes, celery, centipedegrass, cosmos, cucumbers, eggplants, green beans, okra, peanuts, peppers, pumpkins, st. augustinegrass, sweet potatoes, tomatoes, watermelons, winter squash, zoysiagrass, zucchini
April
Plant or sow outdoors: bermudagrass, celery, centipedegrass, cosmos, okra, peanuts, sweet potatoes, zinnias, zoysiagrass
May
Plant or sow outdoors: zinnias
August
September
Start indoors: onions
Plant for fall: bearded irises, broccoli, brussels sprouts, carrots, collard greens, cucumbers, green beans, lettuce, peas, peppers, potatoes, snapdragons, sweet corn, swiss chard, tomatoes, zucchini
October
Start indoors: collard greens, leeks, onions, petunias, ranunculus
Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, carrots, cauliflower, clematis, collard greens, coneflowers, daylilies, hostas, hydrangeas, kale, lettuce, peas, radishes, roses, saffron, snapdragons, spinach, swiss chard, turnips, zucchini
November
Start indoors: black-eyed susans, broccoli, cabbages, cauliflower, chives, collard greens, kale, leeks, lettuce, marigolds, onions, oregano, parsley, petunias, ranunculus, rosemary, sage, snapdragons
Plant for fall: azaleas, bearded irises, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, hydrangeas, kale, kentucky bluegrass, lilies, ornamental alliums, peonies, perennial ryegrass, radishes, roses, saffron, spinach, tall fescue, tulips
December
Start indoors: black-eyed susans, cabbages, cauliflower, chives, cilantro, collard greens, ginger, lettuce, marigolds, nasturtiums, peppers, ranunculus, sage, snapdragons, spinach, swiss chard
Plant or sow outdoors: asparagus, beets, black-eyed susans, blackberries, blueberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, figs, garlic, gladioli, grapes, grass seed, green onions, hollyhocks, kale, kentucky bluegrass, leeks, lettuce, onions, parsley, peas, poppies, potatoes, radishes, ranunculus, raspberries, rhubarb, roses, spinach, strawberries, sweet peas, swiss chard, tall fescue, turnips, wildflowers
Plant for fall: crocuses, daffodils, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips
Frost dates and zones by ZIP code in Glendale
Glendale's 11 main ZIP codes take their frost dates from 2 different NOAA stations. The hardiness zone is 10a in 85310, and 9b in 85301, 85302, 85303, 85304, 85305, 85306, 85307, 85308, 85309, 85355.
| ZIP code | Zone | Weather station | Typical last frost | Typical first frost |
|---|---|---|---|---|
| 85301 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85302 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85303 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85304 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85305 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85306 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85307 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85308 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85309 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
| 85310 | 10a | Phoenix Sky Harbor International Airport, 4.3 mi ESE | Rare | Rare |
| 85355 | 9b | Youngtown, 7.7 mi WNW | Jan 20 | Dec 15 |
Youngtown also supplies the frost dates for Peoria, Surprise and Buckeye, so their planting calendars match Glendale's.
Planting dates for popular crops in Glendale
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Jan 8 to 22 | Mar 5 to 19 | Sep 1 to 8 |
| Strawberries | — | Dec 9 to 23 | — |
| Lettuce | Nov 25 to Dec 9 | Jan 13 to 27 | Sep 15 to Oct 20 |
| Cilantro | Dec 9 to 23 | Jan 20 to 27 | — |
| Basil | Jan 15 to 29 | Mar 5 to 12 | — |
| Potatoes | — | Dec 30 to Jan 6 | Aug 25 to Sep 1 |
| Garlic | — | Dec 9 to 23 | Dec 15 to 29 |
| Onions | Sep 30 to Nov 11 | Dec 23 to Jan 6 | — |
| Cucumbers | Feb 5 to 19 | Mar 5 to 19 | Sep 15 to 29 |
| Pumpkins | Feb 5 to 19 | Mar 5 to 19 | — |
| Peppers | Dec 18 to Jan 15 | Mar 5 to 19 | Aug 25 to Sep 22 |
| Carrots | — | Dec 30 to Jan 20 | Sep 22 to Oct 13 |
| Sweet Potatoes | — | Mar 26 to Apr 2 | — |
| Watermelons | Jan 29 to Feb 12 | Mar 5 to 19 | — |
| Sweet Corn | — | Jan 20 to Feb 3 | Sep 8 to 22 |
| Green Beans | — | Mar 5 to 19 | Sep 22 to 29 |
| Zucchini | Feb 5 to 19 | Mar 5 to 19 | Sep 22 to Oct 6 |
| Broccoli | Nov 4 to 25 | Dec 23 to Jan 6 | Sep 29 to Oct 27 |
| Peas | — | Dec 9 to 23 | Sep 22 to Oct 6 |
| Spinach | Dec 9 to 16 | Jan 13 to 27 | Oct 6 to Nov 10 |
| Sunflowers | — | Jan 20 to Feb 10 | — |
| Zinnias | Mar 22 to 29 | Apr 19 to May 3 | — |
| Tulips | — | — | Nov 3 to Dec 29 |
| Daffodils | — | — | Nov 3 to Dec 15 |
| Grass Seed | — | Dec 9 to 23 | Nov 3 to 17 |
Nearby cities
- Phoenix, AZ zone 9b
- Avondale, AZ zone 9b, last frost Jan 7
- Surprise, AZ zone 9b, last frost Jan 20
- Tempe, AZ zone 9b
- Peoria, AZ zone 9b, last frost Jan 20
- Scottsdale, AZ zone 9b
Planting in ArizonaAbout zone 9bPrintable calendar for Glendale
Questions
When is the last frost in Glendale?
Around January 20 in a typical year, based on NOAA's 1991-2020 records for Youngtown. There is still a 1 in 10 chance of frost after February 18.
What planting zone is Glendale in?
USDA hardiness zone 9b (2023 map), with parts of the city in zone 10a. The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Glendale?
Start seeds indoors January 8 to 22 and set plants out March 5 to 19.
When is the first frost in Glendale?
Around December 15 in a typical year, and before November 28 about 1 year in 10.