What to Plant (and When)

Late summer through early fall is one of the best planting windows in Iowa. From mid-August into early October, you can successfully plant trees, shrubs, perennials, cool-season annuals, spring bulbs, lawns, and a second round of vegetables. Here’s a Central Iowa–specific guide from Holub Greenhouses in Ames to help you plant with confidence.

Why fall planting works so well in Central Iowa

Warm soil + cooler air = faster root growth and less stress. Plants establish now and wake up stronger next spring. For Story County gardeners, use this guide as your timing playbook and keep an eye on your local frost probabilities as fall progresses.

Trees & Shrubs: Build structure now

• Deciduous trees & shrubs: Plant August through early November.
• Evergreens (pine, spruce, etc.): Best mid-August through September so roots establish before winter.
• Watering plan: Water daily for 3–4 days after planting, then taper to a deep soak every 7–10 days in dry weather for 3–4 weeks. Continue until the ground freezes.

This watering plan is designed for Iowa’s climate and helps prevent winter desiccation.

Holub tip: Bring photos of your site (sun, wind exposure). We’ll help you pick species that thrive in Ames neighborhoods and rural windbreaks alike.

Perennials: Plant, divide, and mulch

Late summer into early fall is ideal for planting and dividing many perennial favorites—peony, iris, daylily, garden phlox, and oriental poppy. After planting or dividing, mulch with a few inches of clean straw or pine needles in late fall to reduce freeze-thaw heaving.

Holub tip: Shop our Iowa-tough perennials and ask about spacing for next year’s mature size so beds look full without overcrowding.

Cool-Season Annuals: Fresh color for fall

When marigolds and coleus start looking tired, swap in cool-season annuals. In Iowa, plant mid-to-late September; many tolerate light frost (some down to about 28°F–25°F) and can look good into mid-November or early December, weather-depending.

Holub picks for Ames porches & pots: pansies, violas, snapdragons, ornamental kale & cabbage, dusty miller.

Spring-Flowering Bulbs: Mark your calendar for October

October is prime time to plant tulips, daffodils, and other spring bulbs. Plant in clusters, not single rows, for the biggest visual impact. (You can still plant as late as December if the soil isn’t frozen.)

Holub tip: Grab a bulb auger and bone meal when you pick up bulbs—easy tools for perfect depth and strong roots.

Lawns: Seed now for a lush spring

For cool-season turf, mid-August to mid-September is the best window to seed new lawns or overseed thin areas. Warm soil speeds germination, cool nights drive growth, and weeds are less competitive.

Fall Vegetables: A second (tastier) season

Plan a quick fall harvest of your by staggering sowings:

• Early to mid-August: beets, carrots, Swiss chard, kohlrabi, kale
• Late August to early September: leaf lettuce, spinach
• Mid- to late September: radishes
• October-early November: plant garlic for next summer harvest

For better germination in hot, dry soils: sow a bit deeper than in spring, water the row lightly after seeding, or time sowing right after a rain. Lettuce seeds dislike extreme heat—watch the forecast and sow during a cooler stretch.

Holub tip: We stock fresh seed and fall veggie starts. Ask for shade cloth or row cover if a late-August heatwave hits.

Central Iowa Timing at a Glance

• Now–October: Trees & shrubs (evergreens by late September)
• Now–September: Plant/divide perennials; mulch in late fall
• Mid–late September: Cool-season annuals for color into November/December
• October (can be later if ground isn’t frozen): Spring bulbs
• Mid-Aug–Mid-Sept: Lawn seeding & overseeding
• Staggered Aug–Nov: Fall veggies per list above

Check Ames/Story County frost probabilities as you plan (first 32°F can vary year to year).

Quick Local Planting Checklist

• Soil test or add compost before big plantings
• Set trees/shrubs at correct depth; water deeply and mulch (keep mulch off trunks)
• Label new perennials/divisions and add late-fall mulch
• Refresh containers with cool-season color
• Mark bulb spots now so you plant in October
• Overseed lawn before mid-September; keep seedbeds consistently moist
• Start your fall veggie rows; water lightly and often during germination

Fall Planting FAQs

When should I plant trees in Ames, Iowa?
Plant deciduous trees/shrubs August–early November; evergreens mid-August–September for best establishment. Water regularly until the ground freezes.

What perennials can I divide in late summer?
Peony, iris, daylily, garden phlox, and oriental poppy are good candidates. Mulch in late fall to prevent heaving.

What’s the best month to plant spring bulbs here?
October. Plant in clusters for big impact; you can plant later if soil isn’t frozen.

When do I overseed my lawn in Central Iowa?
Mid-August to mid-September is ideal due to warm soil, cool nights, and lower weed pressure.

Can I still plant vegetables for fall harvest?
 Yes—seed beets, carrots, chard, kohlrabi, and kale in early/mid-August; lettuce/spinach late August/early September; radishes mid-/late September; plant garlic in October–early November.

Visit Holub Greenhouses in Ames

We grow and source plants that love Central Iowa’s climate. Stop by our Ames garden center for locally grown perennials, fall annuals, bulbs, lawn seed, and veggie starts—plus friendly advice from a team that gardens right here in Story County.