When to plant Ageratum in Merced County, CA
Plant Ageratum in Merced County from February 10 to March 3 in spring. Merced County sits in USDA Zone 9a, with last frost around February 24 and first frost on November 28.
When to Plant Ageratum in Merced County, CA
Your July game plan for Merced County, California
July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Merced County, California.
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Basket week: ageratum
If you can't use it all right away, check the food-preservation section of your planner.
Before August arrives, get these ready
- First harvests: ageratum
Ageratum (Ageratum houstonianum), the floss flower, produces clusters of fluffy, powder-puff blooms in the rare sky-blue and lavender tones difficult to find among warm-season annuals. Compact mounding habit makes it ideal as a front-of-border edging plant. Blooms from early summer through fall with minimal deadheading; heat and humidity tolerant once established.
Merced County, California is in USDA Zone 9a. The average last spring frost is February 24 and the first fall frost is November 28, giving you a growing season of approximately 277 days.
At an elevation of 269 feet, Merced County receives approximately 18.8 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Ageratum during the growing season. With low rainfall, drip irrigation is essential for growing Ageratum successfully. Mulch heavily to conserve soil moisture.
Merced County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.7
Drainage
Well Drained
Ageratum Planting Risk Windows
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 Merced County
How your county's soil matches Ageratum's growing requirements.
Soil pH
Your soil pH (6.8–7.7) is more alkaline than Ageratum prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Merced County is excellent for Ageratum — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Ageratum.
How to Plant Ageratum
Succession Planting Ageratum
Sow every 6.9 weeks. Last sowing by Sep 14 to harvest before frost.
Ageratum Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Ageratum
Ageratum needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Ageratum Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.4" | 0" | ❄️ Dormant |
| Feb | 4.3" | 4" | 0.3" | 💧 Light watering |
| Mar | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Apr | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| May | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Jun | 4.3" | 0.1" | 4.2" | 🚿 Regular watering |
| Jul | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Aug | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Sep | 4.3" | 0.2" | 4.1" | 🚿 Regular watering |
| Oct | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Nov | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Dec | — | 3.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in Merced County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Ageratum 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" — every day above 50°F 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.
Ageratum Planting Timeline — Merced County, CA
Ageratum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 13 | Jan 13 – Jan 27 |
| Transplant Outdoors | February 10 | Feb 10 – Feb 24 |
| Direct Sow | February 10 | Feb 10 – Mar 3 |
| Bloom | April 7 | Apr 7 – Sep 22 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Direct Sow |
| April | Bloom |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
60–75 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 9a
📆 Growing Season
277 days in Merced County
Growing Tips for Ageratum in Merced County
Direct sow Ageratum outdoors after February 24 in Merced County when soil has warmed and frost danger has passed.
Common pests for Ageratum in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
Merced County receives only 19" of rain annually. Ageratum needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 6–8 weeks before last frost — do not cover seed; it needs light to germinate. Can be direct-sown after last frost once soil warms to 60°F. Transplant or thin to proper spacing after frost danger passes. Deadheading isn't strictly required but tidying spent clusters improves appearance. Provide consistent moisture; drought causes premature setting. Avoid deep shade — blooms best in full sun to light afternoon shade.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Ageratum in Other Locations
Frequently Asked Questions
When should I plant Ageratum in Merced County, CA?
Merced County is in Zone 9a with an average last frost of February 24. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Merced County, CA?
Merced County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 24 and first fall frost is November 28.
When should I plant Ageratum in Merced County, CA?
In Merced County, CA, plant Ageratum after the last frost (around February 24) and before the first frost (around November 28). Best results when soil holds above 50°F.
What growing zone is Merced County, CA for Ageratum?
Merced County sits in USDA Zone 9a. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.
Can Ageratum grow in Merced County's climate?
Yes — Ageratum grows well in Merced County's temperate climate. Merced County averages a 278-day frost-free season, with last frost around February 24 and first frost around November 28.
Your Merced County Garden Planner — Free
A 22-page printable planner built for Merced County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.