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When to Plant Kai Lan in Rio Arriba County, NM

Kai lan (Chinese broccoli) is a brassica grown for its thick, glossy stems and small flower buds. It has a slightly bitter, broccoli-like flavor essential in Cantonese cooking.

Rio Arriba County, New Mexico is in USDA Zone 5b. The average last spring frost is June 13 and the first fall frost is September 17, giving you a growing season of approximately 96 days.

At an elevation of 5,979 feet, Rio Arriba County receives approximately 17.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Kai Lan to ensure they mature before fall. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Kai Lan will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Kai Lan successfully. Mulch heavily to conserve soil moisture.

Rio Arriba County, NM (Zone 5b) Very short season
96 days
Last Spring Frost June 13
96 growing days
First Fall Frost September 17

Rio Arriba County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (21 days to spare)
Start indoors: May 2 Transplant: Jun 6 🍅 Harvest: Jul 25 – Aug 22
Recommended (50%) ✓ Fits season (19 days to spare)
Start indoors: May 9 Transplant: Jun 13 🍅 Harvest: Aug 1 – Aug 29
Safe Start (90%) ✓ Fits season (18 days to spare)
Start indoors: May 20 Transplant: Jun 24 🍅 Harvest: Aug 12 – Sep 9

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 Rio Arriba County

How your county's soil matches Kai Lan's growing requirements.

Soil pH

Your soil pH (7.3โ€“8.1) is more alkaline than Kai Lan prefers (6.0โ€“7.5). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Rio Arriba County warms quickly in spring but drains fast. Kai Lan will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Kai Lan.

Organic Matter

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

How to Plant Kai Lan

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Kai Lan

2
successive plantings in your 96-day season

Sow every 5.1 weeks. Last sowing by Jul 19 to harvest before frost.

For a dedicated fall crop, sow by Jul 09.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 552 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Kai Lan

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

Month Kai Lan Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 1.1" 0" โ„๏ธ Dormant
Mar โ€” 0.9" 0" โ„๏ธ Dormant
Apr โ€” 0.6" 0" โ„๏ธ Dormant
May โ€” 0.5" 0" โ„๏ธ Dormant
Jun 4.3" 0.5" 3.8" ๐Ÿšฟ Regular watering
Jul 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering
Aug 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Sep 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering
Oct โ€” 1.4" 0" โ„๏ธ Dormant
Nov โ€” 1.2" 0" โ„๏ธ Dormant
Dec โ€” 1.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Rio Arriba County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Kai Lan 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.

Kai Lan needs ~682 GDD — county provides 1,248 GDD Excellent fit

Kai Lan Planting Timeline โ€” Rio Arriba County, NM

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors May 9 May 9 โ€“ May 23
Transplant Outdoors June 13 Jun 13 โ€“ Jun 27
Direct Sow May 30 May 30 โ€“ Jun 20
Harvest August 1 Aug 1 โ€“ Aug 29
Fall Sowing July 9 Jul 9 โ€“ Jul 23

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Start Indoors Direct Sow
June Transplant Outdoors Direct Sow
July Fall Sowing
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

45โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

96 days in Rio Arriba County

Growing Tips for Kai Lan in Rio Arriba County

Direct sow Kai Lan outdoors after June 13 in Rio Arriba County when soil has warmed and frost danger has passed.

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

Common pests for Kai Lan in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

Rio Arriba County receives only 17" of rain annually. Kai Lan needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow in spring or fall. Harvest when flower buds first appear but before they open. Cut stems at the base to encourage side shoots. Prefers cool weather.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kai Lan in Rio Arriba County, NM?

Rio Arriba County is in Zone 5b with an average last frost of June 13. Plan your Kai Lan planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Rio Arriba County, NM?

Rio Arriba County, New Mexico is in USDA Hardiness Zone 5b. The average last spring frost is June 13 and first fall frost is September 17.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Rio Arriba 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 Rio Arriba County, NM. Local conditions may vary. Last updated: April 2026.