How to Transplant Seedlings in 5 Easy Steps

Sowing from seed is a great way to save money and fill your garden with an abundance of flowers, vegetables, and herbs season after season. It also allows you to choose varieties that may not be available in seedling or pot form at your local nursery. If you want something unique and eye-catching, planting from seed is the way to do it.

Depending on the time of year, most seed sowing occurs in trays in a protected area, such as your home or a greenhouse. The process of getting those seedlings from their trays and into the ground to continue growing productively is called transplanting.

Transplanting may seem like a relatively simple process, and generally, it is. However, there are many areas where things can go wrong. If you’re new to planting from seed or have continuous issues with your seedlings after sowing and want to find out why, you’re in the right place.

Here, I’ll take you through how to transplant seedlings in 5 easy steps, along with some aftercare tips to ensure your newly planted crops thrive.

Before You Start

Before you transplant seedlings, it’s important to check that your timing is right. Each crop you grow has slightly different transplanting requirements, which vary depending on the season and conditions they prefer.

Cool-season plants that appreciate moderate temperatures and cannot handle the heat need to be transplanted before temperatures get too hot to give them time to establish. Warm-season crops are sensitive to cold temperatures and cannot be transplanted too early, as frost and temperature dips may kill them off before they get a chance to grow.

You also don’t want to transplant anything too late. Leaving seedlings in their trays can lead to a lack of space and nutrients, causing stems to become leggy. Timing is everything, and you want to avoid transplanting too early or too late.

The easiest way to check this is to read the instructions on your seedling packet. This will tell you when to start and when to transplant based on your last or first frost date, depending on what you’re growing. Once you know your timing is right, you can begin to transplant your seedlings.

How to Transplant Seedlings

Once you’ve checked the requirements of your specific plants and confirmed it’s safe to transplant seedlings, you can begin these steps. They do take a bit of time and aren’t always necessary depending on what you’re growing, but this is the best way to limit damage to your seedlings and ensure they have a strong start.

Step 1: Harden Off

When you’re sowing indoors or in a protected area, your seedlings are used to a controlled environment perfectly curated for germination. Going straight from that cozy environment to the harsh outdoors is bound to lead to shock and stress.

Seedlings aren’t automatically accustomed to outdoor conditions (particularly temperatures, but also factors like wind and differing soil conditions). Hardening off is a process that allows you to slowly introduce them to new environments, allowing seedlings to acclimate before you permanently move them outdoors. Shock and stress can kill off young seedlings or prevent establishment, and hardening off limits the chances of that happening.

To harden off your seedlings, move the tray outdoors for a couple of hours each day, starting with the warmest part of the day. Bring them in overnight and take them out again the next day. Over the course of a week or two, depending on how long you want to harden off, slowly increase the amount of time the seedlings are outdoors until they spend most of their time there.

Initially, depending on what light levels your seedlings have been exposed to, they may be more sensitive to harsh direct sunlight. Start in a protected area and gradually introduce them to direct sun until they are prepared to handle it.

Also make sure they are sheltered from high winds. A gentle breeze is fine and will actually improve the strength of the stems, but any harsh winds can cause them to snap or fall over.

Step 2: Prepare Your Soil

Before your seedlings go into the ground, you need to ensure that the soil is right for the plants you plan to grow. If the soil is too sandy and drains too quickly, seedlings that prefer high moisture levels will struggle to establish. If your soil is heavy clay, roots may struggle to develop and can experience issues with waterlogging and root rot before they take off.

In either extreme, the fix is amending your soil with plenty of compost. This is a good practice to improve soil structure, regardless of soil quality.

If you have homemade compost, mix in a healthy amount a few weeks before you plan on transplanting. If you don’t have your own homemade compost, purchase from a local supplier or amend the soil with any organic matter that will slowly break down to improve soil structure.

Depending on what you’re growing, you generally don’t need to add fertilizers at this time. Excess nutrients in the soil at transplanting time can actually stress seedlings, limiting root growth rather than boosting it. However, this differs depending on what you’re growing, so make sure you check the requirements of your specific plants before you transplant.

Step 3: Space and Create Holes

When you’re sowing seeds in trays, spacing is resolved for you. One or two seeds get popped into a cell, and they germinate happily. However, once they go into the ground, there’s a lot more to consider.

Check the required spacing between plants before getting them in the ground. This spacing is determined by the width of the mature plant, not the size at the seedling stage. Your garden may look sparse after you transplant seedlings, but that’s because they need plenty of room to grow into mature plants.

Planting seedlings too close together can have negative consequences down the line. It increases competition between crops, limiting resources like nutrients, water, and space below the soil line. Lack of space above the soil line also causes issues, as limited airflow encourages the proliferation of pest and disease problems that spread quickly between plants that are too close together.

If you’re growing crops you plan to harvest, spacing is even more important. Competition can reduce output, especially in vegetables that are considered heavy feeders. Closer spacing does allow you to grow more, but the resulting produce will likely be smaller. Again, the seed packet will provide this information for you. Read the spacing instructions and ensure you’re giving your seedlings enough room to develop happily.

Once you’ve decided on your spacing, create a small hole with your hands or with a trowel, ready for transplanting.

Step 4: Handle Carefully

You’ve got your spacing marked and your holes prepared. Now, you simply need to move your seedlings from their trays into the ground. The exact method will depend on the seed-starting process you used. If you’re using cell trays, simply pop them out and plant. If you’ve used soil blocks or biodegradable pots, you can move these into the ground as-is.

The most important thing to consider when transplanting is to handle seedlings carefully. The young roots are fragile and don’t respond well to disturbance. The stems and leaves are also relatively weak early on, so handle them carefully as well.

Some crops struggle to establish after their roots are disturbed. Root crops like carrots are a good example, as any damage to their main taproot will stunt growth later on. For these crops, you should consider direct sowing rather than planting in trays.

However, if you do need to start early (for example, if you live in a cold climate with a short season), sow in biodegradable pots so you don’t handle the roots at all when transplanting.

Step 5: Water Thoroughly

Once your seedlings are in the ground and covered, encourage the roots to grow outwards and downwards into the soil to establish. Deep watering now will encourage new roots to grow deeper into the soil, creating a healthy foundation for later growth.

After planting, water the entire area thoroughly without making it soggy. The soil should drain excess water, leaving enough moisture to satisfy the young roots and prevent stress.

Seedlings are most vulnerable immediately after planting while they acclimate to their new environments. Regular watering during this time will limit further stress, helping them establish well.

After this initial watering, check your seedlings daily and water again when the soil starts to dry out. If you have a large area to cover, consider drip irrigation to ensure that your seedlings are always well-watered.

After Transplanting

After transplanting, seedlings are quite vulnerable. You may notice some slow growth before they take off, which is normal. However, any major discoloration or wilting could indicate an issue at transplanting time.

Keep a close eye out for pests that often attack young, tender growth of new seedlings. Protect them with a row cover if needed until they are strong enough to handle slight pest damage on their own.

If you are transplanting in spring or fall, consider cold protection for young seedlings. Some plants may be cold tolerant once established but need time to mature after transplanting before they reach that level. In that case, use cold protection like a cold frame until all risk of frost and sudden cold snaps has passed, or, until the plants are established enough to manage on their own.

Keep a close eye on your seedlings, but don’t baby them or change conditions too drastically. They need time to settle before they start to grow prolifically. As long as you follow these steps, you should see your new crops take off soon.