Propagation and planting of plants

Grow your own
How do you avoid pre-cultivated seedlings being caught off guard by cold, weather, and wind? And when should you actually move the plants out? Here we delve deeper into the topic of hardening off and transplanting.
Propagation and planting of plants
Liselotte Roll
Written by: Liselotte Roll

Swedish garden inspirer, journalist and author of books about nature, cultivation and animals, such as "Soil", "Grow for insects" and "Chickens as a hobby".

In the spring, when what you have sown indoors fills up window sills, benches, and tables, the longing to get the plants out into the garden is usually strong - but it's important to keep a cool head and wait for the right temperature. Most plants that are started indoors do not tolerate cold well, and just one frosty night can be enough to make them wither. Some plants can tolerate a little frost in the fall, once they have acclimated to living outside, but still be sensitive to cold at the beginning of the season. Other plants may be completely dependent on the temperature not dropping below a certain number of degrees in order to survive. This is the case, for example, with heat-loving cucumber plants, which can collapse completely if you put them outside before the temperature stays above 10 degrees throughout the day. By hardening off the plants, you give them a better chance to survive, handle the transition to outdoor life, and grow strong after being transplanted.

This is how you take care of your plants

Even though the temperature is suitable, many plants need to be hardened off before being planted outside, meaning they need to acclimate to outdoor life slowly and gradually. During hardening off, you bring the plants outside during the day and inside at night. Start by giving the plants a couple of hours outside on the first day and then extend the time outside day by day over a couple of weeks. Placing the plants on a tray makes it easier to move them in and out. By hardening off the plants, you will get stronger plants that can continue to grow despite the change in environment. By covering the new plants with a row cover for the first few weeks after planting them outside, you give them a little extra help - and you also prevent small birds from pulling up the seedlings.

Think about sun and wind

All plants need the sun, but just when the plants are hardened for outdoor life, the sun can sometimes be too powerful. Therefore, avoid putting the plants in the worst sun exposure, and place them in a sheltered spot from the wind, so they can have a calm and nice start outside. Also, be prepared to bring the plants inside if there are frosty nights that you had not anticipated. The weather can vary greatly, and we have seen several frosty nights as late as June. It may be well worth it to keep an eye on the weather forecast.

When should different plants be planted out?

Tomatoes, physalis, most leafy plants, onion plants, and berries These plants can usually be planted outside when the nighttime temperature reaches 8 degrees and the risk of frost is over. However, always read the seed packet you have sown.

Chili can be planted outside when the nighttime temperature reaches 10 degrees and the risk of frost is over. These plants love warmth and thrive best in a greenhouse or in a warm spot facing south. If you plant them outdoors, they will be pollinated naturally by bees and other pollinators.

Cucumber, squash, beans, melon, and eggplant For these plants, the temperature must be above 12 degrees throughout the day before you can plant them outside. Cucumbers do not like drafts, so plant them in a warm and windless place.Basil, lemon verbena, and sweet verbena Here we are talking about really sensitive and heat-loving plants that need a nighttime temperature above 15 degrees to thrive outside.

A good tip when it comes to planting is to investigate where the plants originally come from. If they actually belong to warmer latitudes, can they maybe thrive in the sunniest spot in the garden? This applies, for example, to eggplant, which has its roots in southern India, and chili, which comes from South America. At the other end of the spectrum, you will find vegetables that have been developed to survive in Siberia and in northern latitudes – these still need sun to grow, but can often tolerate a slightly more exposed location.
Topics:
Grow your own

You need help? Ask me!