Transplanting
After nurturing transplants from seed, the tender should be acclimated gently to the late-spring air — known as “hardening off.”
Chris Smith, the community coordinator for Sow True Seed — an Asheville-based company that specializes in open-pollinated, heirloom, and organic seeds — answers common gardening questions.
Last year I had the most beautiful tomato transplants, but when I planted them outside they almost died. What did I do wrong?
There are many seeds that we start indoors so that we can nurture the seedlings and small plants in controlled conditions. This also gives us a jump on the growing season by starting seeds inside 4 to 8 weeks before they are ready to move outside. Tomatoes, peppers and eggplants are great examples of frost-tender, heat-loving plants that benefit from starting indoors.
Around April and May garden centers will begin selling transplants — those 4 to 8 week old plants in pots that are ready to “transplant” to the outdoors. Although you get more choice and more plants when growing from seed, it is great to know that you can still grow your own tomatoes even if you don’t have the time or space to grow your own transplants from seed.
So, why did your tomato transplants nearly die?
Assuming you planted them outside after the frost date, the most likely answer is they were not hardened off properly. Hardening off is the easy yet essential process of slowly acclimating your tender indoor plants to tough outdoor conditions. It is an important step that should not be skipped or rushed. It’s necessary for all transplants — both cold hardy and frost tender ones. If you are buying your transplants, make sure to ask if they have been hardened off.
Simple steps for hardening off:
Hardening off is a gradual process with the aim of exposing the seedlings to increased sunlight, nighttime lows, wind and reduced watering over a 7 to 10 day period.
1. Begin by moving the seedlings to an outside but sheltered spot for just 2-3 hours of sunlight. I like to do this in the morning, on the eastern side of my house.
2. Everyday, increase the amount of sun exposure and slowly reduce the amount of watering. Avoid fertilizing.
3. Monitor the weather. Tomatoes do not want to be exposed to below 65F temperatures. Be careful of strong winds and heavy rains.
Once the plants are happy to be outside all day, they are ready to be transplanted into the garden bed. Be gentle and water well when transplanting to reduce transplant shock. Once settled, a low dose fertilizer can be applied to encourage growth.
I don’t have the time or space to start seeds indoors. Can’t I just sow straight into my garden beds?
The simple answer is yes. In nature, there is no coddling of baby seedlings in perfect conditions — everything is direct seeded. However, there are many benefits for some crops to being started indoors, especially if you want an early start on the season or if your season is short. I like to break my spring-summer plantings into four categories: cold-hardy transplants, cold-hardy direct seeds, tender transplants and tender direct seeds.
Cold-hardy transplants are things like cabbages and broccoli. Cold-hardy direct seeds are things like peas, carrots and beets — note that root crops don’t like being transplanted so much. Tender transplants were covered in the previous question and include tomatoes, peppers and eggplants. Right now, we are fast approaching the last frost date and I am planning my tender direct seeded crops.
To size up your own frost date, try Dave’s Garden online calendar. By entering your zip code, it gives you a sliding scale of frost risk. Here’s mine for Asheville: frost is nearly certain through April 15 and remains likely through April 30, with the risk of frost passed completely by May 16.
This fits with the local wisdom in our area, which says that Mother’s Day is a safe planting date for frost sensitive plants. As you become more experienced you can start pushing the window and use techniques such as row covers and low tunnels to warm the soil and achieve earlier planting dates. Remember that germination is affected by soil temperature, not air temperature.
On or after Mother’s Day, I can confidently direct seed corn, beans, okra, squash, cucumbers and melons. These types of plants actually prefer being direct seeded. They have fast growing root systems and suffer from transplant shock because their roots don’t like to be disturbed once they get going. If you really want to start these types of seeds indoors, use a compostable pot so you don’t have to disturb the roots too much.
Gardening is a matrix of techniques, and direct seeding is easy and effective for many crops.
For more: sowtrueseed.com