We’re beginning to transplant a number of the extra cold-hardy seedlings, akin to cabbage, cauliflower, and broccoli, into the backyard this week. Earlier than we transplant any seedlings, we full a course of generally known as hardening off. 

In your house, your seedlings expertise managed local weather situations. They obtain constant mild, moisture, temperature, and no wind. Once we harden them off, we put together them for the uncontrolled local weather outdoors within the backyard. In case you skip hardening off, transplanting can shock your seedlings, which means that they’ll stunted, fail to thrive, or die from the sudden modifications. 

When and The right way to Harden Off Seedlings

Typically, we begin hardening off seedlings one to 2 weeks earlier than our supreme transplant date. Longer, slower hardening-off durations are often higher, so give it the complete two weeks in the event you can. We begin with simply an hour or two of out of doors time every day and slowly enhance that till the vegetation are able to spend the entire day open air. 

Don’t place your seedlings outdoors on very windy days or when the temperature stays beneath 45°F. These situations can shock even cold-hardy seedlings. 

Hardening Off Issues

Once we take into consideration hardening off our seedlings, there are some things we need to think about: daylight, water, wind, and temperature. Beneath, we’ll dive into handle these components as we harden off our seedlings. 

Daylight

Your indoor lights are nice for beginning seedlings however aren’t as harsh because the pure daylight your vegetation will face within the area. 

To start hardening them off, set them out in a shady, sheltered location for one to 2 hours per day. Steadily transfer them to sunnier areas and enhance the period of time they spend open air. 

Water

Vegetation within the area in all probability received’t obtain the identical constant moisture they obtained beneath your watchful eye indoors. Often, letting seedlings dry out however not wilt will assist them adapt.

Wind

Your tender seedlings have by no means handled any wind in your own home. Begin them outdoors in a sheltered location and keep away from placing them out on very windy days. Whereas your seedlings are nonetheless indoors, you possibly can mimic the wind by gently brushing the tops together with your hand.

Temperature

Sticking seedlings out as quickly as we’ve had a number of heat days may be tempting, however you need to keep away from damaging your vegetation. Don’t harden off seedlings when temperatures are beneath 45°F. Some vegetation will fail to supply if uncovered to chilly temperatures in a single day. 

For instance, broccoli could “button up” or solely produce tiny heads if the seedlings expertise temperatures beneath 20°F. These chilly temperatures make the broccoli assume it has gone by means of winter and is time to flower. 

Cucumbers and melons may cease rising if the temperatures get too chilly. Deliver them in at night time till temperatures keep above 50°F.

In case your space continues to be experiencing chilly temperatures, putting your seedlings in a low tunnel, chilly body, or hoop home can present a buffer and assist them slowly adapt to cooler temperatures. 

Transplanting Ideas

• Transplant on an overcast or cloudy day. 
• Guarantee your soil is free, and add compost to the mattress or planting gap.
• Loosen the roots on any root-bound vegetation.
• Water seedlings effectively.
• Place mulch round seedlings.

It may be tempting to haul your vegetation out to the backyard and put them within the floor on a sunny day. Nonetheless, benefiting from your vegetation requires a bit of extra preparation. Hardening off your seedlings is important to thriving crops.