If you want a successful garlic harvest next summer, knowing when to plant garlic in Pennsylvania is the most important step. Getting the timing right gives your cloves the best chance to establish roots before winter, leading to bigger, healthier bulbs.
This guide will walk you through the optimal planting windows for different Pennsylvania regions, how to prepare your soil, and the simple steps for planting and care.
When to Plant Garlic in Pennsylvania
The short answer is fall. Garlic needs a period of cold dormancy, called vernalization, to properly develop bulbs. Planting in autumn allows the cloves to develop roots before the ground freezes, then they go dormant over winter. As soon as spring warmth arrives, they burst into growth.
The ideal planting time is typically 2-4 weeks after the first fall frost, but before the ground freezes solid.
This usually means a window from mid-October through mid-November for most of the state. The goal is to get roots established, but not so much top growth that it gets damaged by hard frosts.
Pennsylvania’s Climate Zones and Planting Dates
Pennsylvania spans USDA Hardiness Zones 5a to 7b, which affects your local timing.
Zone 5 (Northwestern PA, higher elevations):
* First frosts arrive early, often in early October.
* Optimal Planting: Early to mid-October. Aim to get cloves in the ground by Halloween.
Zone 6 (Central PA, including State College, Harrisburg area):
* This is the most common zone in the state.
* Optimal Planting: Mid-October to early November. A good target is around the last week of October.
Zone 7 (Southeastern PA, including Philadelphia suburbs, parts of the Lehigh Valley):
* Warmer winters and later frosts.
* Optimal Planting: Late October through mid-November. You can often plant successfully into late November here.
A classic gardener’s rule is to plant garlic around the same time you would plant your spring-flowering bulbs, like tulips.
Choosing Your Garlic Type: Hardneck vs. Softneck
The type of garlic you choose also influences your planting and harvest.
Hardneck Garlic
* Best for: Most of Pennsylvania, especially zones 5 and 6. They are more cold-hardy.
* Characteristics: Produces a hard central stalk (the “scape”) that should be removed in early summer to boost bulb size. They have fewer, larger cloves per bulb and a more complex flavor range. The skins are easier to peel.
Softneck Garlic
* Best for: Warmer areas of Zone 7 and for gardeners who want to braid their garlic.
* Characteristics: More cloves per bulb, stores longer (often up to a year), and does not produce a woody scape. They are generally less cold-hardy than hardnecks.
For most Pennsylvania gardeners, hardneck varieties like ‘German White’, ‘Music’, or ‘Chesnok Red’ are excellent, reliable choices.
Step-by-Step Guide to Planting Garlic
Follow these steps for a successful planting.
1. Source Your Seed Garlic.
* Always buy “seed garlic” from a reputable nursery or farm. Grocery store garlic is often treated to prevent sprouting and may not be suited to our climate.
* Choose firm, healthy bulbs. You’ll separate them into individual cloves just before planting.
2. Prepare Your Planting Bed.
* Garlic needs loose, well-draining soil rich in organic matter. It hates wet, soggy feet.
* Pick a spot with full sun (at least 6-8 hours).
* Work in several inches of compost or well-rotted manure a few weeks before planting. A balanced organic fertilizer can be mixed in at this time too.
3. Prepare and Plant the Cloves.
* Gently break the bulb apart, keeping the papery skin on each clove.
* Select the largest, healthiest cloves for planting. The smaller cloves can be used in the kitchen.
* Plant cloves pointy end up, root side down.
* Depth: 2 inches deep in heavier soils, up to 3 inches deep in sandy soils.
* Spacing: 4-6 inches apart in rows that are 12 inches apart.
4. Mulch Heavily.
* After planting, water the bed well if the soil is dry.
* Then, apply a 4-6 inch layer of loose mulch like straw, shredded leaves, or grass clippings. This is crucial in Pennsylvania to prevent frost heaving, suppress weeds, and retain moisture.
* The mulch will protect the cloves through the winter.
Caring for Your Garlic Through the Seasons
Winter:
* Sit back and let nature do its work. The mulch is protecting your cloves.
Spring:
* As shoots emerge in March or April, you can gently pull back some mulch if it’s very thick, but leave it in place as a weed barrier.
* Side-dress with a nitrogen-rich fertilizer (like blood meal or a balanced organic fertilizer) when growth is about 6 inches tall.
* Keep the soil consistently moist, but not waterlogged, through spring and early summer.
Early Summer (for Hardnecks):
* In June, hardneck garlic will send up a curly flower stalk called a scape. Cut or snap it off once it makes one full curl. This directs the plant’s energy back into the bulb.
* Don’t throw them away! Garlic scapes are a delicious seasonal treat, great in pestos or stir-fries.
Harvest Time (Summer):
* Garlic is usually ready in late June or July. Watch for the lower leaves to turn brown while the top 5-6 leaves are still green.
* Do not wait for all the leaves to die back. That means the bulbs may have begun to split.
* Gently loosen the soil with a garden fork and lift the bulbs. Avoid pulling by the stem.
Curing and Storage:
* Brush off excess dirt, but don’t wash the bulbs.
* Cure them in a warm, dry, airy place out of direct sun for 3-4 weeks (like a garage or covered porch).
* Once the necks are completely tight and dry, trim the roots and stems. Store in a cool, dark place.
Common Mistakes to Avoid
* Planting too early: Planting in September can cause too much top growth that winter cold will damage.
* Planting too shallow: This can lead to frost heave pushing the cloves out of the ground.
* Skipping mulch: Mulch is non-negotiable for a good Pennsylvania garlic crop.
* Overwatering in summer: As harvest nears, reduce watering to let the bulbs mature and prevent rot.
* Using grocery store garlic: It’s simply not worth the disappointment of poor results.
FAQ: Planting Garlic in Pennsylvania
Q: Can I plant garlic in the spring in PA?
A: You can, but results are often disappointing. Spring-planted garlic misses the crucial cold period. Bulbs will be much smaller, often single cloves (called “rounds”). Fall planting is always recommended.
Q: What if I miss the fall planting window?
A: If the ground is still workable, plant immediately. You can try planting into December if a thaw occurs, but cloves may not root well. Your best bet is to store your seed garlic in a cool, dark place and try again next fall.
Q: How do I deal with pests?
A: Garlic has few pest problems. The main issue in our area can be onion thrips. A strong spray of water from the hose can dislodge them. Good weed control and crop rotation are the best preventions for any disease.
Q: Can I grow garlic in containers?
A: Yes! Use a deep pot (at least 12 inches) with excellent drainage. Follow the same planting depth and timing. Containers may need extra winter protection, like moving them to an unheated garage, as they freeze faster than in-ground soil.
Q: Why did my garlic produce small bulbs?
A: Common causes are planting too late, not enough sun, poor soil fertility, overcrowding, or not removing scapes from hardneck varieties. Ensuring you follow the correct timing for when to plant garlic in Pennsylvania is the first place to look.
Getting your garlic in the ground at the right time sets the stage for an easy, rewarding harvest. With just a bit of fall effort, you’ll be set for a summer full of your own homegrown flavor.