If you’re a New Jersey gardener, knowing when to plant flowers is the key to a vibrant, successful garden. The best time for planting depends heavily on what you’re planting and your specific location in the Garden State. This guide will break down the ideal planting windows for annuals, perennials, bulbs, and more, helping you create a beautiful bloom schedule from spring to fall.
When to Plant Flowers in NJ – Best Time for Planting
New Jersey’s climate falls within USDA Hardiness Zones 6a to 7b, which means we experience cold winters and warm, humid summers. This range creates two primary planting seasons: spring and fall. Getting your timing right protects tender plants from frost and gives new plants the best conditions to establish strong roots.
Understanding New Jersey’s Planting Seasons
Our weather can be unpredictable, with late frosts in the north and earlier heat in the south. Always check your local frost dates as a starting point. The average last spring frost ranges from early April in south Jersey to mid-May in the northwest. The first fall frost typically arrives from early October to late October.
Spring Planting (After the Last Frost)
This is the main season for planting most summer-blooming flowers. The soil is warming up, and there’s plenty of time for plants to grow before summer’s peak heat.
- Target Window: Late April through early June.
- Best For: Tender annuals, summer bulbs, and warm-season perennials.
- Key Rule: Wait until the danger of a hard frost has completely passed. A light frost might still occur, so be prepared to cover newly planted tender blooms.
Fall Planting (Before the First Frost)
Fall is an excellent, often overlooked, planting season. The soil is still warm, the air is cooler, and there’s usually more rainfall. This allows plants to focus on root growth without the stress of summer heat.
- Target Window: Early September through mid-October.
- Best For: Spring-blooming bulbs, hardy perennials, trees, and shrubs. You can also plant cool-season annuals like pansies for fall color.
- Key Rule: Get plants in the ground at least 6 weeks before the ground freezes to ensure good root establishment.
Planting Calendar for Popular New Jersey Flowers
Here’s a more specific breakdown by plant type. Remember, these are general guidelines—microclimates in your own yard matter too.
Annual Flowers
Annuals complete their life cycle in one season and are typically frost-sensitive. They provide instant color.
- Warm-Season Annuals (Petunias, Marigolds, Zinnias, Impatiens): Plant outdoors in mid to late May. You can start seeds indoors 6-8 weeks before your last frost date.
- Cool-Season Annuals (Pansies, Snapdragons, Ornamental Kale): These can tolerate light frosts. Plant them in early spring (April) or in the fall (September) for color when other plants fade.
Perennial Flowers
Perennials come back year after year. Planting time affects how quickly they establish.
- Spring-Blooming Perennials (Peonies, Bleeding Heart, Dianthus): The best time to plant is in early fall. This gives them a full season to root before they need to flower. You can also plant them in early spring as soon as the soil is workable.
- Summer-Blooming Perennials (Coneflower, Black-Eyed Susan, Daylilies): Plant in spring after the last frost or in early fall. Avoid planting during the intense summer heat unless you can provide consistent water.
Bulbs
Bulbs are categorized by when they bloom, which dictates when you plant them.
- Spring-Blooming Bulbs (Tulips, Daffodils, Crocus, Hyacinths): Plant in the fall, from late September through November. The soil needs to be cool (below 60°F) so they can develop roots without sending up shoots.
- Summer-Blooming Bulbs (Dahlias, Gladiolus, Cannas, Lilies): These are often not winter-hardy in NJ. Plant them in the spring after the last frost (May). You’ll need to dig up and store tender bulbs like Dahlias in the fall after the first frost blackens their foliage.
Step-by-Step Guide to Planting Flowers in NJ
Once you’ve got your timing right, proper planting technique ensures your flowers thrive.
- Prepare the Soil: New Jersey soil can be heavy clay or sandy. Amend your planting beds with 2-3 inches of compost or well-rotted manure to improve drainage and fertility. Loosen the soil to a depth of about 12 inches.
- Check Plant Needs: Group flowers with similar sunlight and water requirements together. Always check the plant tag for its mature size to avoid overcrowding.
- Dig the Right Hole: For potted plants, dig a hole twice as wide as the root ball but no deeper. The top of the root ball should be level with the soil surface. For bare-root plants, build a small mound in the hole and spread the roots over it.
- Plant and Backfill: Gently remove the plant from its container, tease out any circling roots, and place it in the hole. Backfill with the native soil mixed with compost, gently firming it as you go to remove air pockets.
- Water Deeply: Give your new plant a thorough, slow watering immediately after planting. This helps settle the soil around the roots. Continue to water regularly for the first few weeks until its established, especially if rainfall is scarce.
- Add Mulch: Apply a 2-3 inch layer of organic mulch (like shredded bark or leaves) around the plant, keeping it a few inches away from the stem. This conserves moisture, suppresses weeds, and regulates soil temperature.
Regional Considerations Within New Jersey
Our state may be small, but its gardening conditions vary. Here’s what to keep in mind:
North Jersey (Zones 6a-6b)
- Shorter growing season and later last frost (often mid-May).
- Start spring planting 1-2 weeks later than southern regions.
- Fall planting should be done by early October to ensure root establishment before colder weather.
Central Jersey (Zones 6b-7a)
- A moderate climate with a good balance.
- Follow the general timelines outlined above, using your local frost dates as a guide.
- Be mindful of summer humidity, which can promote fungal diseases on some flowers.
South Jersey & Coastal Areas (Zones 7a-7b)
- Longer growing season and earlier last frost (often early to mid-April).
- You can start spring planting 1-2 weeks earlier.
- Coastal areas benefit from milder winters but can have sandy, fast-draining soil that requires more ammendments.
Common Mistakes to Avoid
- Planting Too Early: Impatience leads to frost damage. Resist the urge to buy tender annuals at the first garden center display in April unless you can protect them.
- Ignoring Soil Prep: Skipping soil amendment is a major reason plants struggle. Good soil is the foundation of a healthy garden.
- Overcrowding: Plants need air circulation to stay healthy. Give them room to reach their mature size.
- Forgetting to Harden Off: If you start seeds indoors or buy plants from a greenhouse, you must acclimate them to outdoor sun and wind over 7-10 days before planting them in the ground.
FAQ: Planting Flowers in New Jersey
What month do you start planting flowers in NJ?
You can start planting hardy flowers like pansies in early April. The main planting month for most summer flowers is May, after the last frost. Fall planting for perennials and bulbs is best in September and October.
Is it better to plant flowers in spring or fall in New Jersey?
It depends on the plant. For most perennials, shrubs, and spring bulbs, fall is actually ideal because the plant focuses on root growth. For tender annuals and summer bulbs, spring is the only option. Both seasons have there advantages if you time it right.
What flowers can I plant now in NJ?
Check your current season and frost dates. In early spring, plant cool-season annuals and bare-root perennials. In late spring, plant warm-season annuals. In fall, focus on spring bulbs, perennials, and cool-season annuals for fall color.
When should I plant perennials in NJ?
The best times are early fall (September) or early spring (April). Fall planting is often prefered as it gives the plant a longer establishment period before the summer stress. Avoid planting during the hot, dry months of July and August.
Can I plant flowers before the last frost?
Only frost-tolerant or “hardy” flowers like pansies, snapdragons, and some perennials can be planted before the last frost date. Always check the plant’s specific tolerance and be prepared to cover them if a surprise late frost is forecasted.
By aligning your gardening tasks with New Jersey’s natural rhythms, you set your flowers up for success. Paying attention to frost dates, your specific zone, and the needs of each plant type will lead to a garden that flourishes with color and life throughout the growing season. Remember, gardening is a learning process—each year provides new insights for the next.