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When to Plant Medlar in Los Alamos County, NM

Medlar is a small ornamental tree producing unusual open-ended fruits that must be bletted (softened by frost) before eating. The flavor is complex, like spiced apple butter.

Los Alamos County, New Mexico is in USDA Zone 6a. The average last spring frost is May 10 and the first fall frost is October 7, giving you a growing season of approximately 150 days.

At an elevation of 5,220 feet, Los Alamos County receives approximately 12.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87ยฐF, providing good warmth for Medlar during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Medlar will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Medlar successfully. Mulch heavily to conserve soil moisture.

Los Alamos County, NM (Zone 6a) Moderate season
150 days
Last Spring Frost May 10
150 growing days
First Fall Frost October 7

Los Alamos County Soil Profile

Soil Type

Sandy Loam

Soil pH

7-8.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 23
Recommended (50%) ✓ Fits season
Transplant: May 31
Safe Start (90%) ✓ Fits season
Transplant: Jun 16

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 Los Alamos County

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

Soil pH

Your soil pH (7.0โ€“8.6) is more alkaline than Medlar prefers (6.0โ€“7.5). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Los Alamos County warms quickly in spring but drains fast. Medlar will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Medlar.

Organic Matter

Organic matter is low (0.8%). Add 2-3 inches of compost before planting Medlar.

How to Plant Medlar

120"
Between Plants
144"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.3″/week
You supply
1.2″/week
Watering frequency 2-3 times/week
Season total 1,540 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Medlar

Medlar needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Medlar Needs Rainfall You Supplement Action
Jan โ€” 0.9" 0" โ„๏ธ Dormant
Feb โ€” 0.6" 0" โ„๏ธ Dormant
Mar โ€” 0.8" 0" โ„๏ธ Dormant
Apr โ€” 0.4" 0" โ„๏ธ Dormant
May 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Jun 4.3" 0.4" 3.9" ๐Ÿšฟ Regular watering
Jul 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Aug 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Sep 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Oct 4.3" 1.1" 3.2" ๐Ÿšฟ Regular watering
Nov โ€” 0.7" 0" โ„๏ธ Dormant
Dec โ€” 0.8" 0" โ„๏ธ Dormant

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

Medlar 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.

Medlar needs ~22,265 GDD — county provides 2,287 GDD May not mature

Medlar Planting Timeline โ€” Los Alamos County, NM

Medlar Planting Calendar

Activity When Date Range
Transplant Outdoors May 31 May 31 โ€“ Jun 14

ยท 120" apart ยท Rows 144" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

1095โ€“1825 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

150 days in Los Alamos County

Growing Tips for Medlar in Los Alamos County

Direct sow Medlar outdoors after May 10 in Los Alamos County when soil has warmed and frost danger has passed.

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

Your 150.0-day growing season in Los Alamos County is tight for Medlar (1095.0-1825.0 days to maturity). Start indoors and choose early-maturing varieties.

Los Alamos County receives only 12" of rain annually. Medlar needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant in well-drained soil. Medlars are self-fertile and need minimal pruning. Harvest after the first frost and allow to soften (blet) indoors for 2-3 weeks before eating.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Medlar in Los Alamos County, NM?

Los Alamos County is in Zone 6a with an average last frost of May 10. Plan your Medlar planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Los Alamos County, NM?

Los Alamos County, New Mexico is in USDA Hardiness Zone 6a. The average last spring frost is May 10 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Los Alamos County gardeners in Zone 6a 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 Los Alamos County, NM. Local conditions may vary. Last updated: April 2026.