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Do Cabbage Seedlings Need To Be Hardened Off

You may think that growing seeds to seedlings is one of the best ways to start a healthy crop. In many ways, it is – as long as you do it right. Before planting your seedlings, you should ask, do cabbage seedlings need to be hardened off?

Yes, cabbage seedlings need to be hardened off. If you do not harden off your cabbage plants, they may be shocked by the temperature and element change and die or not grow.

Hardening off seeds is how you introduce seedlings to the temperature changes and wind, rain, and sunlight outside. Seedlings grown inside are grown in a steady climate, so you’ll want to become an expert on seedlings, so you don’t kill your seedlings!

4 Benefits Of Hardening Off Cabbage Seedlings

Hardening off seedlings gives the cabbage seedlings the best chance at survival and growing into healthy cabbage crops.

Seedlings Are Introduced To Different Temperatures

Hardening off your cabbage seedlings means that your cabbage seedlings will be introduced to different temperatures.

When you grow seeds and seedlings inside, your seedlings will always be in the same conditions. The temperature is relatively consistent; no extreme or sudden temperature changes occur outside.

If your seedling is not hardened off, a sudden temperature change may shock your seedling to the point that it will die.

Plus, cabbage is a cold-weather plant, so the frost or cold temperatures could destroy your seedlings before you even have a chance of getting cabbage.

Seedlings Won’t Die In Sunlight, Wind, Or Rain

Seedlings aren’t exposed to too much sunlight, wind, or rain inside, which is not the same outside.

Again, seedlings are not used to sun, wind, and rain when grown outside.

Now, you can’t help your seedling withstand the random elements outside, but hardening off your cabbage seedling can help your seedling survive better outside.

Your cabbage seedling will become stronger and healthier when you plant them. 

Leaves Will Lose Less Water

Hardening off your leaves will help your cabbage’s leaves get thicker and keep water in.

The leaves are thin and delicate when you first transplant or grow a seedling.

If you put a plant like this outside after being hardened, your plant leaves can become thicker and more hardy. 

This also means that your plant is less likely to lose water through its leaves, so your seedling will not dry out faster than expected. 

Cabbage Seedlings Are Less Likely To Die

Overall, the hardening of your seedling is less likely to die.

The best thing that comes from hardening off your seeds is that your cabbage seedlings are not as likely to die.

Look at this chart to understand how much your cabbage seedlings can benefit from being hardened off:

Hardened Off?Outcome
YesSeedlings will have a better change at survival. As the seedling grows, you will see that it starts to have growth within 1-2 months.
NoYour seedling may quickly die or have its growth stunted if it is not hardened off before being planted outside. This can happen within a week, but the effects may not be seen for weeks.

How Do You Harden Off Cabbage Seedlings 

Hardening off your cabbage is not as complex as you might think. Take the extra time to help your cabbage seedlings survive!

Step 1: Plan To Harden Off Seeds 1-2 Weeks Before Planting

You will need to plan when you want to harden off your seedlings.

Begin to harden off your cabbage seedlings about 7-14 days before you plan to plant your seedlings outside.

This will give you ample time to harden off your cabbage seedlings without rushing the process. 

Step 2: Begin Placing Your Seedlings Outside For One Hour

You’ll first begin to place your seedlings outside.

At first, you will only put your seedlings outside for one or two hours. 

Remember: You are doing this to introduce your cabbage seedlings to different temperatures, so you don’t want to shock your seedlings this early in the process.

You also do not want to yet put your seedlings into too much sunlight. 

Step 3: Slowly Increase The Time Your Seedlings Spend Outside

Start to increase the time that your seedlings spend outside in different temperatures.

After the first few days, you can start to keep your seedlings outside for a little longer each time.

Since your cabbage seedlings are now getting used to the temperature differences, you can also put your plants in the sunlight.

Do not put your cabbage seedlings into direct sunlight for too long; again, cabbage are cool weather plants, so you do not want to scorch your cabbage seedlings.

Step 4: Leave Plants Overnight

After 7 or 8 days, you can leave your plants outside overnight.

The next step is to put your cabbage seedlings outside to experience the world when the temperature dips when it is dark.

Your cabbage will be outside for 10-12 hours, but as long as you start slowly by introducing your cabbage seedlings to daytime temperature, your seedlings will be okay. 

Do not put your cabbage seedlings outside if you know there will be a frost. This extreme temperature will be enough to shock and kill your cabbage seedling. 

Step 5: Transplant Your Seedlings

And that’s it! You’ve successfully introduced your cabbage siblings to the outside world, so you are ready to transplant your seedlings. 

Keep the following things in mind when you are transplanting your cabbage seedlings:

  • Let your seedlings grow a few adult leaves before transplanting
  • Give each cabbage plant about 18 inches between each plant to avoid overcrowding 
  • Keep closer to 2 feet of place between rows of cabbage plants
  • Water your cabbage plants around the roots for a healthy soaking

Congratulations! You’re well on your way to having a healthy crop of cabbages at the end of the growing season.