Friday, March 8, 2013

When is it Warm Enough to Plant?

Hey Everyone,

With the warmer days of spring just around the corner, everyone will be anxious and eager to get out and enjoy his or her garden.  I hope that many will want to try direct sowing some seeds.  I ran across this chart on the Gardener's Supply website and thought we would all appreciate the guidelines for soil temperature to ensure good germination rates.  Remember the green dots are far from optimum and will produce results that are more erratic.

The best temperatures for starting seeds
When is it Warm Enough to Plant?

To obtain the most success with direct sowing seed, it is important to follow a few simple steps.


Bed 50 is a wonderful example of
well worked soil with
a nice loam to it. 
  • Take the time to do a little garden prep work.  Thoroughly check your bed for the presence of any undesirables (grubs, cutworms, vine borer larvae, etc.).  Turn in plenty of soil amendments (free compost is available) and work the soil so it is a nice loose consistency with no heavy clumps of dirt. Fertilize properly and level the bed nice and neat. 
  • Look for the seasonal benchmark.  The best advice I ever received was to look for the sweet spot when planting.  This is a great weekend for prepping the soil and then letting the bed rest a few days to a week before sowing.  When turning your bed, you will be bringing the cooler soil to the top and it will take a few days to warm.  We can still have harsh weather and some young seedlings will easily succumb to the freezing temperatures.  Tip:  Unless you are using a frost blanket, it is still too early for sowing carrots, beets, turnips, and lettuce.  However, it is a perfect time for bulbing onions, peas, parsley, radishes, spinach, and mustard greens.  I will start taking soil temperatures this weekend and post them so we have an idea of where things stand.  Temps taken this afternoon ran approx. 37.3 to 41.6 degrees depending on where you were in the garden. Those who have consistently been covering were substantially higher by 10 to 12 degrees.

    Freshly watered soil with
    a desirable loam and consistency. 
  • Follow the seed packet instructions for the depth and spacing requirements.  Some seeds require light to germinate and if sown too deep will not sprout.  A nice rule of thumb is to sow no more than two to three times as deep as the seeds diameter.  However, if your packet states to barely cover the seeds, follow these instructions.   
  • Keep the seedbed evenly moist and do not let it dry out. Use a fine mist or shower nozzle to prevent dislodging of the seeds and eroding of the soil.  Tip: Nothing hinders the process more than allowing the seedbed to dry out during germination.  I actually try to mist my bed roughly the same time every day to ensure success.  
  • Make sure to know what your seedlings will look like and mark them properly.  Pull all competing spring weeds as they have the potential to harbor disease and insects as well as compete for your seedlings nutrients.  Once sprouted, gradually wean to your regular watering schedule, however, please remember raised beds do dry out rapidly and young seedlings need consistency. 
The attached sowing guides should get everyone off to a wonderful season of growing.  Devra at Botanical Interests has been kind enough to give me their permission to use these charts for our garden needs!  They have excellent recommendations for good germination rates of what is safe to put in now and what you should wait a bit on.  If I can be of any assistance, please don't hesitate to ask or post a comment.


Enjoy the wonderful weather this weekend!                                              

Denise, Beds 25 & 29

2 comments:

VickiBed41 said...

It will be interesting to watch the temperatures as the week goes by. I'm assuming if we do get rain Monday, that will make the soil cooler, right? But it does look like we have 10 days of really warm temperatures ahead of us.

Pack-rat said...

I took some temps today, will take some tomorrow, and will take Tuesday after Monday's rain. I actually don't completely know that answer Vicki. I do know when I took temps in my own bed immediately after watering, I lost 3 degrees. However, I figured that would be due to the water still being so cold in the ground. Sounds like something to check.......