A Guide to Seeding Vegetables in Spring

Planting seeds at the ideal time boosts the success of your garden and lets you enjoy the fruits of your labor as early as possible.

 

The planting season is quickly arriving to the eager gardeners of Glenside, but if you want to ensure a vibrant garden this year, a bit of careful planning is needed before you can start playing in the dirt again. In this guide, we’ll walk you through which seeds to plant in the spring and when to plant them, whether you’re starting them indoors or planting them directly in your garden!

 

Part 1: Cool Season Vegetables to Seed Outside 

Cool-season crops thrive in the milder temperatures of spring and fall. They tolerate varying degrees of frost and can be planted before Glenside’s last frost date, usually around April 15-30. Here’s a list of some of Pennsylvania’s most popular cool-season veggies and the best times to seed them:   

Arugula is a fast-growing salad green you can plant outdoors as soon as the soil can be worked, typically in mid-March. With its peppery flavor and tender leaves, arugula is a favorite for fresh salads and sandwiches.

 

Broccoli is a hardy, cool-season vegetable that can be directly seeded outside once the soil is workable, though some gardeners prefer to start them indoors and transplant them after the risk of frost has passed. This method allows the seedlings to grow faster sooner, whereas starting them outside in the early spring yields a bit of a slower beginning. 

Beets can be planted outdoors in March as soon as the soil is adequately thawed. Their sweet, earthy flavor makes them perfect for roasting, pickling, and adding to salads.

Bok choy is a fast-growing Asian green that can be planted outdoors once the soil is workable. With its mild flavor and crunchy texture, bok choy is perfect for stir-fries and salads.

Brussels sprouts are absolutely packed with vitamins and minerals. They grow best when planted in early spring, typically early to mid-April. 

Cabbage is a cool-season crop that can be planted outdoors as soon as the soil can be worked, typically in mid-March. Featuring a crisp texture and mild flavor, cabbage is perfect for coleslaw, sauerkraut, and cooked dishes.

Carrots are root vegetables that can be planted as soon as the ground is workable. However, their root growth requires that the soil not be too wet or compacted, so be sure to wait until it’s dry and loose. 

Cauliflower is a well-loved member of the cabbage family that tolerates light frost, so make sure the risk of deep frost has passed before planting. Mid- to late-April is usually the best time for seeding this cool-season crop.

 

Celery can be seeded outside in mid to late April. With its crisp texture and mild flavor, it’s perfect for salads, soups, and snacks.

Collards are ready to be directly sown in your garden around mid-March to early April. They’re renowned for their rich flavor, tender texture, and high levels of vitamins and minerals. 

Kale is a cold-hardy vegetable that can be planted outdoors as soon as the soil is ready. Packed with essential nutrients and offering great flexibility in recipes, kale is an indispensable asset to any garden.

Lettuce thrives in cooler temperatures and can be planted outdoors in mid-March. With its rapid growth and variety of leaf shapes and colors, lettuce is a versatile addition!

Mustard greens are a spicy green that can be planted outdoors as soon as the soil allows. Mustard greens, with their peppery flavor and easy-growing nature, add an early-season kick to salads and cooked dishes.

 

Onions are a cool-season crop that can be seeded outside as soon as the ground is workable. Prized for their intense flavor and culinary versatility, onions are a staple in many savory dishes.

Peas are cool-season staples that can tolerate frost and should be planted as soon as the soil is workable, typically in mid-March to early April. These sweet and tender legumes are cherished for fresh snacking and for adding a fresh pop to salads and stir-fries.

Potatoes are another cool-season crop that can be planted as early as mid-March. They are perfect for roasting, mashing, and frying. Like carrots, they need loose soil for rooting, so make sure the ground has dried before planting.

Radishes are one of the first vegetables you can sow directly in the ground. These fast-growing root vegetables add a zesty crunch to salads and mature quickly, making them perfect for impatient gardeners!

Spinach is another cold-hardy green that can be planted outdoors once the ground has thawed and is dry enough to be worked. Packed with vitamins and minerals, spinach is a nutritious addition to salads, smoothies, and cooked dishes.

 

Swiss chard is a colorful and nutritious green that can be planted outdoors as soon as the soil can be worked, typically in mid-March. 

Turnips are a lesser appreciated but valuable cool-season crop that can be planted outdoors as soon as the soil is workable. With their sweet and earthy flavor, turnips are perfect for roasting, steaming, and mashing.

 

Part 2: Warm Season Crops to Start Indoors 

In contrast to their cool-season counterparts, warm-season crops are incredibly susceptible to frost. They can die if exposed to freezing temperatures. Therefore, it’s necessary to wait until the risk of frost has completely passed before planting these vegetables outdoors. However, most of them can be started indoors while you wait. Here’s when and how to plant them for the most success!

Cucumbers can be planted outdoors in May or June after the danger of frost has passed us by. These green machines are perfect for salads, pickling, and snacking. Because they are sensitive to transplant shock, it’s best to seed them outside directly rather than starting them indoors. 

Eggplants are a warm-season crop that should be started indoors 8-10 weeks before the last frost date. With their creamy texture and mild flavor, eggplants are perfect for grilling, roasting, and sautéing.

 

Green beans can be planted outdoors as soon as the risk of frosty weather has safely passed. Their crisp texture and mild flavor make them perfect for steaming, sautéing, and stir-frying.

Melons are a warm-season fruit that can be planted outdoors after the last frost date in May. A crown jewel of any garden, melons are perfect for refreshing snacks and desserts.

Peppers should be started indoors 8-10 weeks before the last frost date and transplanted. Whether you like them sweet or spicy, peppers are perfect for grilling, stuffing, and adding to sauces.

Pumpkins are warm-season giants that can be planted outdoors once Glenside’s frosty weather has ended. They are a favorite for pies, soups, and Halloween decorations. Though they have sensitive roots, they germinate and grow quickly outside, meaning it’s best to seed them directly in the ground once the weather is warm enough. 

Squash is another warm-season vegetable that can be safely planted outdoors once the danger of frost has passed. These veggies are perfect for soups, stews, and roasted dishes. Like with pumpkins, their sensitive roots mean that direct seeding outside is best for these gourds. 

 

Tomatoes are a warm-season fruit that should be started indoors 6-8 weeks before the last frost date. With their juicy flesh and rich flavor, tomatoes are a favorite for salads, sandwiches, and sauces.

As you wait for your seeds to yield their first harvest, don’t forget to savor the many edible weeds that flourish in the early season, such as dandelion, chickweed, and common plantain. These superfoods are the first greens of the year and can be mixed into salads with other vegetables to cut their strong flavors. 

For all your seed needs, or for more advice on what to seed in the spring, don’t hesitate to visit our garden center in Glenside, PA!