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When to Plant Feverfew in San Juan County, NM

Feverfew is a bushy perennial herb with small daisy-like flowers and aromatic leaves. It has been used traditionally for headache relief and is a cheerful garden plant.

San Juan County, New Mexico is in USDA Zone 5b. The average last spring frost is May 12 and the first fall frost is October 6, giving you a growing season of approximately 147 days.

At an elevation of 8,301 feet, San Juan County receives approximately 14.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87ยฐF, providing good warmth for Feverfew during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Feverfew will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Feverfew successfully. Mulch heavily to conserve soil moisture.

San Juan County, NM (Zone 5b) Short season
147 days
Last Spring Frost May 12
147 growing days
First Fall Frost October 6

San Juan County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 12 🍅 Harvest: Aug 11 – Oct 27
Recommended (50%) ✗ May not fit
Transplant: May 19 🍅 Harvest: Aug 18 – Nov 3
Safe Start (90%) ✗ May not fit
Transplant: Jun 9 🍅 Harvest: Sep 8 – Nov 24

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in San Juan County

How your county's soil matches Feverfew's growing requirements.

Soil pH

Your soil pH (7.3โ€“8.5) is more alkaline than Feverfew prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in San Juan County warms quickly in spring but drains fast. Feverfew will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Feverfew.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Feverfew.

How to Plant Feverfew

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.4″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 379 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Feverfew

Feverfew needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Feverfew Needs Rainfall You Supplement Action
Jan โ€” 1.1" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 0.8" 0" โ„๏ธ Dormant
Apr โ€” 0.5" 0" โ„๏ธ Dormant
May 2.2" 0.3" 1.9" ๐Ÿšฟ Regular watering
Jun 2.2" 0.5" 1.7" ๐Ÿšฟ Regular watering
Jul 2.2" 2.5" 0" โœ… Rainfall sufficient
Aug 2.2" 2.6" 0" โœ… Rainfall sufficient
Sep 2.2" 2.2" 0" โœ… Rainfall sufficient
Oct 2.2" 1.3" 0.9" ๐Ÿ’ง Light watering
Nov โ€” 0.8" 0" โ„๏ธ Dormant
Dec โ€” 0.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in San Juan County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Feverfew Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Feverfew needs ~1,601 GDD — county provides 2,241 GDD Excellent fit

Feverfew Planting Timeline โ€” San Juan County, NM

Feverfew Planting Calendar

Activity When Date Range
Transplant Outdoors May 19 May 19 โ€“ Jun 2
Harvest August 18 Aug 18 โ€“ Nov 3

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June Transplant Outdoors
July โ€”
August Harvest
September Harvest
October Harvest
November Harvest
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

147 days in San Juan County

Growing Tips for Feverfew in San Juan County

Direct sow Feverfew outdoors after May 12 in San Juan County when soil has warmed and frost danger has passed.

Sandy soil in San Juan County dries quickly โ€” mulch Feverfew with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Feverfew in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

San Juan County receives only 14" of rain annually. Feverfew needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors or direct sow on the soil surface. Deadhead regularly to prevent aggressive self-seeding. Divide clumps every 2-3 years to maintain vigor.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Feverfew in San Juan County, NM?

San Juan County is in Zone 5b with an average last frost of May 12. Plan your Feverfew planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is San Juan County, NM?

San Juan County, New Mexico is in USDA Hardiness Zone 5b. The average last spring frost is May 12 and first fall frost is October 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help San Juan County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for San Juan County, NM. Local conditions may vary. Last updated: April 2026.