Greenly Garden

Last and first frost dates in Saguenay

Canada

In Saguenay the last spring frost usually comes around 14 May and the first autumn frost around 22 October, which leaves about 161 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground from 10 June to 2 July.

Last spring frostaround 14 May
First autumn frostaround 22 October
Frost-free days161 days

Median of 2016–2025 for the 25 km grid cell of the city: the last day at or below 0 °C in spring and the first in autumn (ERA5 reanalysis via Open-Meteo). In a cold year a frost can come a week or two later — Greenly warns 48 hours ahead.

When is the last frost in Saguenay?

The last frost in Saguenay usually comes around 14 May: that is the median of 2016–2025, so in about half of those years the last night at or below 0 °C came later. Hardy crops start before it and frost-tender ones only after it: in the table below arugula can go into open ground from 23 April, while corn waits until 28 May. The first autumn frost follows around 22 October, about 161 days later: harvest or cover frost-tender crops before then.

When to sow and plant

CropSow for seedlingsPlant out in a greenhouseOpen ground
Achocha22 March – 14 July1 May – 23 August22 May – 23 August
Ageratumfrom 25 March—from 10 June
Arugula——sow 23 April – 17 September
Basil4 May – 20 August11 June – 27 September2 July – 27 September
Beet——sow 23 April – 23 August
Bell Pepper12 April – 3 May11 June – 2 July2 July – 2 July
Black-eyed Susanfrom 28 February—from 22 May
Bok Choy27 March – 31 August1 May – 5 October22 May – 5 October
Borage——sow 21 May – 28 August
Broad bean——sow 23 April – 14 July
Broccoli——sow 23 April – 7 July
Brussels Sprouts16 February – 4 June2 April – 19 July23 April – 19 July
Busy Lizziefrom 26 February—from 21 May
Cabbage——sow 23 April – 14 June
Calendula——sow from 23 April
Carrot——sow 23 April – 30 July
Cauliflower19 February – 7 July2 April – 18 August23 April – 18 August
Celeriac13 February – 4 May1 May – 20 July22 May – 20 July
Celery13 February – 14 May1 May – 30 July22 May – 30 July
Celosiafrom 12 Aprilfrom 27 Mayfrom 17 June
Chamomile——sow 23 April – 18 August
Chayote8 February – 27 April7 May – 24 July28 May – 24 July
Chickpea——sow 23 April – 4 July
Chicory8 March – 29 July—23 April – 23 August
Chili Pepper12 April – 9 June11 June – 8 August2 July – 8 August
China asterfrom 20 Aprilfrom 11 Junefrom 2 July
Chives——sow 23 April – 9 August
Cilantro——sow 23 April – 19 August
Corn——sow 28 May – 4 July
Corn poppy——sow from 23 April
Cosmosfrom 12 Aprilfrom 27 Mayfrom 17 June
Cucumber14 May – 10 July11 June – 7 August2 July – 7 August
Daikon——sow 23 April – 16 August
Delphiniumfrom 2 February—from 23 April
Dill——sow 23 April – 29 August
Edging lobeliafrom 27 February—from 22 May
Eggplant12 April – 3 May11 June – 2 July2 July – 2 July
Florence fennel17 March – 14 July1 May – 28 August22 May – 28 August
Foxglovefrom 15 January—from 23 April
Garden sorrel——sow 23 April – 17 August
Green Beans——sow 17 June – 12 July
Hollyhock——sow from 23 April
Hyssop——sow 23 April – 10 July
Kale——sow 23 April – 11 August
Kiwano18 April – 17 July20 May – 18 August10 June – 18 August
Kohlrabi——sow 23 April – 21 August
Leek22 January – 25 April2 April – 4 July23 April – 4 July
Lemon balm——sow 23 April – 13 August
Lettuce——sow 23 April – 26 August
Lisianthusfrom 5 Januaryfrom 2 Aprilfrom 23 April
Lovage——sow from 23 April
Luffafrom 30 Aprilfrom 11 Junefrom 2 July
Marigoldfrom 20 Marchfrom 1 Mayfrom 22 May
Marjoram12 April – 29 July—2 July – 27 September
Melon14 May – 27 June11 June – 25 July2 July – 25 July
Microgreens——sow 17 June – 8 October
Moringa29 April – 3 August23 June – 27 September14 July – 27 September
Moss rosefrom 5 March—from 21 May
Mustard greens——sow 23 April – 7 September
Napa cabbage29 March – 8 August1 May – 10 September22 May – 10 September
Nasturtiumfrom 24 Marchfrom 1 Mayfrom 22 May
Okra30 April – 22 July11 June – 2 September2 July – 2 September
Oregano1 February – 19 July2 April – 17 September23 April – 17 September
Pansyfrom 5 Februaryfrom 2 Aprilfrom 23 April
Parsley——sow 23 April – 7 August
Parsnip——sow 23 April – 26 June
Peanut5 May – 17 June11 June – 24 July2 July – 24 July
Peas——sow 23 April – 9 August
Petuniafrom 9 Aprilfrom 11 Junefrom 2 July
Physalis5 April – 14 June20 May – 29 July10 June – 29 July
Pumpkin30 April – 27 June11 June – 8 August2 July – 8 August
Purple coneflowerfrom 30 January—from 23 April
Radish——sow 23 April – 22 September
Sage12 February – 15 July2 April – 2 September23 April – 2 September
Scarlet sagefrom 29 March—from 10 June
Snapdragonfrom 27 Januaryfrom 2 Aprilfrom 23 April
Soybean——sow 2 July – 3 August
Spinach——sow 23 April – 28 August
Stevia1 April – 5 June20 May – 24 July10 June – 24 July
Stock——sow from 23 April
Sunflower——sow from 17 June
Sweet alyssum——sow from 23 April
Sweet Corn18 April – 29 July10 May – 20 August31 May – 20 August
Sweet peafrom 19 Februaryfrom 2 Aprilfrom 23 April
Sweet William——sow from 23 April
Swiss Chard——sow 23 April – 23 August
Thyme——sow 23 April – 4 July
Tomato29 March – 11 May20 May – 2 July10 June – 2 July
Turnip——sow 23 April – 25 August
Watercress——sow 23 April – 5 September
Watermelon14 May – 15 June11 June – 13 July2 July – 13 July
Zinniafrom 19 Mayfrom 23 Junefrom 14 July
Zucchini21 May – 15 July11 June – 5 August2 July – 5 August

Planting out: a week after the last frost once the soil is warm enough for the crop; frost-hardy crops three weeks before it; an unheated greenhouse three weeks earlier. Seedlings are sown so they are ready on that day. Each window starts on the Greenly calendar date and ends on the last day that still leaves the crop’s days to harvest (from its card) before the average first autumn frost, plus six weeks of picking for crops harvested over weeks (tomatoes, peppers, aubergines, cucumbers, courgettes, pumpkins, watermelons, beans) — our rule; earlier in the window is safer.

When the soil warms up in Saguenay

The day the top 7 cm of soil first averages each temperature over a week, median of 2016–2025 (ERA5 via Open-Meteo). The soil reaches 10 °C 8 days after the last spring frost and 15 °C 27 days after it.

SoilDateAgainst the last spring frost
5 °C11 May3 days earlier
10 °C22 May8 days later
15 °C10 June27 days later
18 °C2 July49 days later

Frost dates near Saguenay

Of the nearest cities on our list, the last spring frost ends earliest in Montreal (27 April) and latest in Sherbrooke (8 May).

CityDistanceLast spring frostFirst autumn frost
Quebec City180 km5 May28 October
Trois-Rivières257 km29 April29 October
Sherbrooke343 km8 May27 October
Montreal377 km27 April1 November
Fredericton432 km30 April28 October

What to grow at home in winter in Saguenay

Frosts in Saguenay usually come from about 22 October to about 14 May. These plants have indoor care in their Greenly cards and are harvested quickly, so they can be sown on a windowsill in winter.

Weather in Saguenay by month

Average weather in Saguenay over 2016–2025: the warmest month is July. Months that average 20 °C or more by day: June (21.7 °C), July (24.2 °C) and August (23.1 °C). Nights average below 0 °C in November–April (-16.3–-2.8 °C). About 1239 mm of rain falls in a year, on 162 days; July is the wettest month (173 mm) and January the driest (63 mm).

MonthDay, °CNight, °CRain, mmRainy days
January-8-16.36313
February-6.7-15.96313
March-0.4-9.37712
April6.4-2.87613
May15.94.410011
June21.711.413814
July24.214.817316
August23.114.114414
September18.91011813
October11.94.412614
November2.5-3.78715
December-4.8-12.77414

Average of the daily highs and lows, rain per month and days with at least 1 mm (ERA5 via Open-Meteo, the same grid cell as the frost dates).

Planted in autumn

CropWhen to plant
Bearded Irisby 22 September
Crocus22 September – 30 October
Daffodil22 September – 30 October
Garlic22 September – 30 October
Grape hyacinthby 22 September
Helleboreby 22 September
Hyacinth22 September – 30 October
Lilyby 22 September
Ornamental onionby 22 September
Peonyby 22 September
Saffronby 22 September
Snowdropby 22 September
Tulip22 September – 30 October
Wild garlicby 22 September

From a month before the first autumn frost, so the roots grow before winter, to the late-planting limit on each crop’s page (about two weeks before the ground freezes, by ten years of weather).