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How to Start Cucumber Seeds Indoors (Step by Step)

If you've always wanted to start cucumber seeds indoors, but didn't know how this guide is perfect for you and features 5 easy steps to get started!
Prep Time5 minutes
5 days
Total Time5 days 5 minutes
Keyword: backyard gardening, growing cucumbers, How to Cucumber Seeds Indoors
Author: The Farm Girl Blog

Ingredients

You will need

  • Organic Cucumber Seeds
  • Seedling Starter Kit
  • Starter Soil Mix

Instructions

How to Start Cucumber Seeds Indoors (Step by Step)

  • Step 1: Know When to Start Your Cucumbers
  • Planting cucumber seeds outdoors should begin about two weeks after the last expected frost date. Cold and frost can hurt cucumbers, so the weather needs to warm up a bit before they can be planted safely.
  • But starting your cucumber seeds indoors will give you a head start on the growing season since you can easily control and manage the temperature indoors! And this is why it's my preferred way of doing it.
  • Your cucumber plants will have plenty of time to grow and mature inside if you start your seeds around four weeks before the final expected frost date. Also, it ensures that they will be ready for transplanting about the time you would often begin planting cucumbers.
  • You can, however, start them even early if you like. But keep in mind that the earlier you start, the more time you will have to devote to indoor care before you can transfer them outside.
  • Step 2: Fill Containers with Seed Start Mix
  • Now let's start growing our seedling cucumbers from scratch!
  • First things first, fill the container with seed starter mix or use organic potting soil mix. I personally get it from Costco for fraction of the cost and I highly recommend you do that as well.
  • Make sure not to use garden soil which often drains poorly and may carry disease. Gently press the soil to remove air pockets.
  • Step 3: Sow Cucumber Seeds and Water Lightly
  • Next, use your finger to poke small holes about a quarter-inch deep for each seed. Place one seed in each hole. Then sprinkle additional soil to cover the holes with seeds about a half-inch thick.
  • Once again gently firm the sprinkled soil mix and water lightly. It's highly important to make sure not to flood the container with water.
  • Step 4: Place Container in a Warm Place
  • Finally, place a container in a warm, sunny spot that receives full sunlight. I personally prefer to place my starter trays on the window sill. Ensure that the temperature is at least 70 F (21 C) to 80 F (27 C).
  • Alternatively, you can also place them on a seedling heating mat in a place that's free from drafts and make sure to maintain the temperature I've mentioned above, which is 70 to 80 degrees Fahrenheit (21 to 27 degrees Celsius).
  • Step 5: Monitor and Check Daily
  • Cucumber seeds can take up to 7-14 days to germinate. Monitor the soil moisture level as you wait for the seedlings to emerge.
  • Check daily to keep the planting mix moist but not saturated. Once you see the first sprout keep the seedling at high light exposure or set it on the window sill that gets lots of direct sunlight.
  • Continue keeping the planting seed moist but not soggy.