Tips for Transplanting Seedlings
Are you ready for the first big hurdle of the gardening season? Here’s how to make sure that your seedlings transplant successfully into the garden.
To Seed or Not To Seed
Many home gardeners prefer to start their gardens from nursery-grown transplants rather than from seed. In some respects, this allows for greater flexibility, as you can simply go out and buy the transplants when you’re ready. The downside of this method is that your garden is limited to the varieties available near you, so there may be less overall variety in the plants that you can grow.
On the other hand, starting plants from seed indoors can be a challenge! If you aren’t able to provide them with proper lighting and moisture, they may not be strong enough to survive the move to outdoors. One benefit of starting from seed is that it’s usually cheaper to buy a packet of seeds than it is to buy transplants, and the unused seeds will likely last you two or three seasons.
Whichever technique you choose, you’ll eventually need to transplant your young plants into the garden. Here are some tips for doing so!
Tips for Transplanting
1. Plan Ahead
Timing is important when it comes to transplanting: transplant too early in spring and your plants may succumb to frost, transplant too late and your plants may get baked in the sun (and the opposite is true in autumn). In any case, it’s important to pay attention to local weather conditions.
- First, check our Planting Calendar to see spring frost dates in your area. The date of the last spring frost is commonly used as a guideline for both starting seeds and planting transplants outdoors.
- Know what conditions your plants grow best in. Some plants, such as peas and spinach, are cool-season crops, which means that they should be planted before outdoor temperatures get too warm. Others, like tomatoes and peppers, are warm-season crops and will be weakened by too-cool temperatures. Find advice for individual plants in our library of Growing Guides.
- If you start your plants from seed, it’s a good idea to keep track of when you start them and when you transplant them. This will help you plan in future years!
- Keep an eye on local weather forecasts as you prepare for transplanting. If a serious cold snap is imminent, hold off on transplanting until temperatures are more agreeable.
2. Prepare the Garden and the Plants
When the weather looks like it’s taking a turn for the better, start getting your garden and the plants ready:
- During the transplants’ last week indoors, withhold fertilizer and water less often to condition them to life outdoors.
- Before being planted into the garden, transplants should be “hardened off“ outdoors in a sheltered area:
- 7 to 10 days before transplanting, set the seedlings outdoors in dappled shade that is protected from wind for a few hours each day, gradually increasing their exposure to full sun and windy conditions. This will get them better accustomed to eventually living full-time outdoors.
- Keep the soil moist at all times during the hardening-off period. Dry air and spring breezes can result in rapid water loss.
- Anything that raises the temperature of the soil will help plants adjust to the shock of the cold ground. Try using raised planting beds and plastic mulch or landscaping fabric to boost soil temperature before planting.
- Your garden soil may have become compacted over winter, so loosen and aerate the soil before planting. Add fresh soil if necessary; it should capture and retain moisture, drain well, and allow easy penetration by seedling roots. Read more about preparing soil for planting.
3. Plant Outdoors
Finally, it’s time to transplant!
- If possible, transplant on a warm, overcast day in the early morning. This gives the plants a chance to settle into the soil without being instantly exposed to the intense midday sun.
- Soak the soil around new seedlings immediately after transplanting in order to settle the roots.
- If the season is particularly dry, spread mulch to reduce moisture loss.
- To ensure that phosphorus—which promotes strong root development—is available in the root zone of new transplants, mix two tablespoons of a 15-30-15 starter fertilizer into a gallon of water (one tablespoon for vining crops such as melons and cucumbers), and give each seedling a cup of the solution a few days after transplanting.
- Watch the forecast for late spring frosts and plan to protect your plants accordingly. Cloches, cold frames, or sheets can be used to protect plants. Be sure to remove protective coverings in the morning.
How to Transplant: Step by Step
Check out this video to learn how to take your seedlings from potting tray to garden plot, step by step.
What tips do you have for transplanting seedlings? Let us know in the comments!
Looking to grow a certain vegetable, fruit, or flower? Check out our collection of Growing Guides for plant-specific advice.
Learn how and when to transplant your vegetable plant seedlings outdoors with these instructions from The Old Farmer’s Almanac.