When to plant tomatoes in Knoxville: 5 April – 23 July

In Knoxville, tomato: sow for seedlings from 22 January to 1 June; plant into a greenhouse from 15 March to 23 July; plant out into open ground from 5 April to 23 July. For plants and seeds, the places nearby include Plush Moon Terrarium (garden centre, 2 km) and Mayo Garden Center (garden centre, 6 km); addresses and opening hours are below.

Tomato in Knoxville: soil, season and weather

In Knoxville frost, not soil, sets the date: the top 7 cm of soil warms to 15 °C — the minimum on the tomato card — around 3 April, 5 days after the last frost on 29 March, so planting waits only for the week after that frost.

Last spring frost	29 March
Top 7 cm of soil at 15 °C	3 April, 5 days after the last frost
Into an unheated greenhouse	15 March – 23 July; March outside: 5.2 °C at night, 16.7 °C by day; card 16–27 °C
First autumn frost	12 November, 221 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	14 June – 1 October
Days left for picking	151
Daylight	10:47 on 12 February, 12:43 on 5 April
Watering outdoors when fruiting (card)	every 3 days; the driest month, November, has 8 rainy days

Tomato in Knoxville: care after planting

Planted on 5 April: in the first weeks water every 4 days.

Feeding, by the card’s schedule from that day:

5 April — feed: balanced (NPK)
3 May — feed: nitrogen

Pests and diseases of tomato to watch for:

Dates count from the first planting day of the window above; a later planting moves them by as many days.

Weather in Knoxville during the tomato season

Days average above the tomato card's 16–27 °C in June–September (28.3–31.6 °C). Months that stay below 16 °C even by day on average: November (15.7 °C). Nights average below 16 °C in April, May and October, November (5.1–14.5 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
April	20.8	9	108	11	13:05
May	25.3	14.5	115	13	14:03
June	29.6	18.6	82	12	14:35
July	31.6	21.3	87	14	14:23
August	30.2	20.1	111	14	13:33
September	28.3	17.5	85	9	12:27
October	22.7	11.3	87	7	11:19
November	15.7	5.1	77	8	10:17

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

Around Knoxville, Athens (United States) is 17 days earlier and Asheville 29 days later.

City	Distance	Date	Difference
Asheville	130 km	4 May – 13 July	29 days later
Chattanooga	156 km	28 March – 23 July	8 days earlier
Greenville	184 km	26 March – 2 August	10 days earlier
Athens (United States)	229 km	19 March – 2 August	17 days earlier
Lexington	231 km	28 April – 18 July	23 days later
Atlanta	249 km	22 March – 2 August	14 days earlier

Where to buy tomato plants and seeds near Knoxville

Buy plants ready to set out from 5 April to 23 July (from 15 March to 23 July for an unheated greenhouse); seed for raising your own is sown from 22 January to 1 June. Within 15 km of Knoxville OpenStreetMap lists 7 garden centres, 1 plant nursery and 5 markets (collected 20 October 2026).

Mayo Garden Center — garden centre
Kingston Pike 4718, 37919 · Mon–Sat 09:00–18:00; Sun 00:00–17:00 · 6 km · mayogardencenters.com
Kirby Plants — garden centre
Oak Ridge Highway 7234, 37931 Knoxville · 15 km · kirbyplants.com
Plush Moon Terrarium — garden centre
East 5th Avenue 1423, 37917-7713 Knoxville · Thu–Fri 17:00–20:00; Sat 12:00–18:00; Sun 12:00–16:00 · 2 km
Lovedays Garden Center — garden centre
Chapman Highway 8105, Knoxville · 11 km

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.

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