Hardening Off Flower Starts

You may recall that I started flower and vegetable seeds indoors under lights back in February and March, and now the flowers are about ready to go outside and find their way into my hanging baskets and containers for this growing season.  There is a step that has to be done prior to planting those baby plants out, however, and that is hardening them off. 

Here are some of the flower starts inside:

This is a tray full of:  Zinnia ‘State Fair Mix’ and ‘Giant Lime’, along with Coleus ‘Black Dragon’ and ‘Rainbow Mix’, as well as a ‘Sunset Wizard’.  I started these seeds indoors from February 16th to March 1st in 4″ pots, and they are now filling the pots and are ready to go through the hardening off process.  (Where we live, I like to plant my baskets and containers by May 15th, so this is the right time to start the flower seeds so that the plants are ready to go into the outdoor containers on time.)  So far, these plants have been living the lush life indoors, with consistently warm temperatures and even moisture provided by me.  If I was to just go and plant them outside now, they would likely go through a great deal of transplant shock, which would stunt their growth and either kill them outright or weaken them considerably.

Instead, what I am doing is that every day, I put my trays of seedings outdoors in a protected spot:

  This way, they will have a chance to get used to cooler temperatures, and deal with coping under a little rain and gentle breezes.  This particular spot gives them partial shade and cover from strong winds, which helps to protect them and helps them make the transition to outdoor living a little easier without stressing the plants too much.   The weather has been cool and overcast, which is good weather for hardening off plants because it reduces stress on them as well.  They tend to dry out faster outdoors, so they do require a watchful eye to give them water as needed, so they don’t wilt.  Over the course of a week or two, I take them outside in the morning and bring them inside in the evening, and eventually I leave them outside for longer periods of time and expose them to sunshine (that is, if we ever get any here), culminating in their having a sleep-over outside, all night long for the last day or two of the hardening-off process.  When I leave them outside overnight, I usually put them on this cement area, which will conduct a little solar heat and make it a bit warmer for them than if I put the tray directly on the ground.  (Also the slugs have a harder time getting to them on cement because they first have to go up the stairs, another benefit.)  Once they can get through that, they are ready to plant in my awaiting containers and baskets. 

Those with good eyesight may have seen that I have a couple of tomato starts in with this bunch that I am hardening off.  You are right–I have a couple of early producing  ‘Gardeners’ Delight’ cherry tomatoes that I am going to plant outdoors in a couple of weeks, but because it’s still really too cold for these sun-lovers, they will be swaddled in Wall O’Waters and plastic around them as well.  (Can you tell that I am really hungry for the first tomatoes of the year?)  If the weather is not too uncooperative, it will give us some tomatoes a couple of weeks earlier than normal, a good reward for getting through this wet and cold spring!

That’s it from me–what is new in your garden?  Drop me a line in the comments if you wish!  And visit the Garden Party.



  1. May 10, 2011 at 7:03 pm

    Oohhh purty!! I’m always way behind on my flower seedlings! *sigh* Yours look fabulous!

  2. minervasgardenwriter said,

    May 10, 2011 at 9:59 pm

    Thanks! It took me a lot of mistakes and trial and error to finally figure out when it was the right time to start the seeds inside, and that helped a lot.

  3. Candi said,

    May 11, 2011 at 7:01 pm

    This is our 3rd year so we’re still learning too!

  4. Beth said,

    May 12, 2011 at 1:29 am

    Zinnias and Coleus – love them both – growing from seed you are going to get alot bang for your buck!

    • minervasgardenwriter said,

      May 12, 2011 at 8:14 pm

      Yes, I was hoping that would be the case. I definitely have a lust for coleus, and could never afford to buy as many as I wanted, so I started growing them myself from seed a few years ago, and have done so ever since. They’re pretty easy to grow from seed, luckily!

  5. Teresa said,

    May 12, 2011 at 10:14 pm

    Slugs are the worst for me! They’re eating everything I grow… I was looking around for a good repellent and came across this video: http://youtu.be/cMssG-66oTE

    It’s hilarious! I hope you enjoy it 🙂 It almost made me forget my slug problem…


    • minervasgardenwriter said,

      May 13, 2011 at 3:50 am

      Okay, that was funny! Thanks for sharing!

  6. May 17, 2011 at 2:58 am

    Oh, I’m the worst with hardening things off- it’s my weakest link in the whole seed-to-food cycle. 🙂 Your flowers look fabulous, btw- and I totally relate to the lack of sun!

    • minervasgardenwriter said,

      May 17, 2011 at 7:38 pm

      I had a crazy time of it earlier this year trying to harden off some lettuce and onion starts. The weather was terrible, and I ended up having to haul plants in and out of the house for over 3 weeks before it eventually warmed up and dried out enough for me to plant!

  7. Bill Mous said,

    May 23, 2011 at 4:08 pm

    Is it possible that someone can help me locate a 2 page article, with photographs, on pelargoniums that appeared in the September 16th 2010 issue of the Oregonian? Thank you and have a nice day. Bill

    • minervasgardenwriter said,

      May 23, 2011 at 4:16 pm

      Hi Bill: I would think that you might find it online in an archive at the Oregonion website. Otherwise, you might want to contact the Oregonian’s garden writer–his name is Vern Nelson, and his contact information is usually listed with his gardening articles, which I believe appear in the Thursday edition of the paper. Otherwise, just give the newspaper a call, and they can very likely help you get a copy.

      Good luck!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: