Module 4: Dig in! Planting the garden

In this lesson, we’ll take the mystery out of deciding which seeds to start indoors, when to plant seeds indoors, and techniques to sowing seeds outdoors. We’ll also cover key factors you need to consider when adding transplants to your garden.

After this lesson you will be able to:

  • Describe direct seeding and transplanting 
  • Identify the pros and cons of both

Direct sow or transplant?

Transplants

  • Crops that require a longer period to maturity need to be started indoors, because our growing season is too short. These include tomatoes, peppers, and eggplants. You’ll need to transplant long season crops. If you are starting your own, timing is very important. You don’t want vines a foot long or plants in flower indoors.
  • Transplants get ahead on shading out germinating weed seeds. 

Direct sow

  • Some crops resent transplanting. Examples include root crops like carrots, and legumes (beans and peas).
  • Direct sow leafy greens, crops with big seeds (corn, beans, squash) or long taproots. 
  • Some plants best for succession planting should be direct sown.

Not sure if you should direct sow or start indoors? Check the seed package. Note: whether you direct sow or start indoors, when you purchase seeds rather than transplants, the cost per plant is less and you will find a larger choice in varieties.

When to plant?

  • When considering which crops to grow when, remember there is more than one growing season. Cool crops prefer cooler growing temperatures.
  • Some cool crops will bolt when the temperatures are too warm, or will refuse to germinate. Bolting is going to flower. Often, crops become very bitter once they bolt.
  • In Wausau, the last typical frost is May 14th, First is Sept 28 and the growing season is “typically” 136 days. This will vary from year to year.
  • Remember late summer is a great time to plant for fall cool season crops. Fall peas, spinach, etc.

Reading a seed packet

  • General Seed type. This is the type of crop. 
  • Specific Cultivar (Cultivated Variety).
  • Distance between mature plants: Proper spacing is important so plants will not compete for resources and for air circulation to prevent certain diseases.
  • Number of days for germination: Lets you know how long to expect seeds to take to germinate. Include this time when deciding when to start seeds, especially indoors. 
  • Starting indoors vs direct sowing: Some plants need more time to mature than our season allows. Tomatoes are an example and need to be started indoors. Other plants resent transplanting. Root crops like carrots and parsnips and legumes do not take well to transplanting and should be direct sown. 
  • Days to harvest: Days to harvest can vary depending on cultivar. 
  • Year of seed packaging: If seeds were kept cool, dark, and dry, they may be good for several years. Seeds will generally lose some viability with time, so if you are using 1 year+ seeds, be sure to plant extra seeds. 
  • How deep to sow the seeds: If seeds are buried too deep, they may fail to sprout. Some seeds require light to germinate. The seed package will let you know if this is the case.
  • Soil temp for germination: Seeds need moisture and warmth to germinate. If the soil is too cold, the seed may rot. 

Direct sowing techniques

To prepare the seedbed, add compost or fertilizer broadcasted to the top.  Loosen soil. Work fertilizer and compost in. Rake smooth

  • Create your row in the seed bed with your finger or the end of a gardening tool. 
  • Keep in mind the seed depth on the packet.  
  • For large seeds (beans, corn), plant one by one according to the spacing on the seed packet. For small seeds, tap the seeds out of the packet with your index finger, or you can sprinkle them using your thumb and forefinger.
  • Sow twice what you need! Some won’t germinate and some seeds will be eaten. Don’t forget to thin out once they germinate. 
  • Row planting may be a disadvantage if you have limited space.

  • Sowing in a wider row gets around the wasted space issue.
  • Small crops do best in banded plantings. You can evenly broadcast the seeds, then later thin.

  • Small mound with a few seeds.
  • Good for planting larger crops, vining crops.
  •  Poke 4-5 holes in the mound at the depth needed for the type of seed. Cover.
  •  Once they germinate, thin to 2-3 plants. Later thin to 1 plant.
  •  Distance between plants should be the same as the final footprint of a mature crop.

  • Less in heavy soils, or cover with a potting mix. 
  • What might happen if the seeds are planted too deep? Answer in chat. (May not germinate.)
  • What might happen if the seeds are planted too shallow? Answer in chat. (May wash away or get eaten.)

  • You want the soil to be moist, but not soggy.
  • Use the mist setting on the hose nozzle if you have one.
  • Let water start to puddle, then wait for water to become absorbed, then water gently again until evenly moist. This is especially important in clay soils.

  • Why?
    • To give the seedling room to grow. 
    • Competition of resources. 
    • Easy targets for disease and pests. 
  • Be ruthless! Pick the weaker seedlings, leaving the strongest ones.
  • Don’t pull! Use scissors and cut at soil level.
  • Water well after thinning.
  • Some seedling leaves can be eaten as baby/microgreens. 

Planting transplants

  • Look for stocky, disease free with thick stems and deep green color.
  • Leggy plants are susceptible to disease and pest damage.
  • You want well developed roots, but not rootbound roots. Tap the root ball into your hand to look at the roots. 
  • 2 plants in a pot? Try to separate. You can be very brutal to tomatoes, but some plants resent having their roots manipulated. If they are too intertwined, choose the healthiest one and cut the rest at soil level.

  • Start in dappled sun and give them more sun each day. Do this for a week.
  • In the morning or evening.
  • Prevents transplant shock and wilting. 
  • Water the transplants several hours before planting.

  • Dig the hole wider and slightly deeper than the root ball.
  •  Add fertilizer/compost at the bottom of the hole and mix into the soil.
  •  Bottom bottom leaves at top of planting hole. 
  • Exception- tomatoes. 
  • Water gently, but well. First watering will settle pockets of air. Add more soil if the soil sinks down. Keep well watered in the first week. 

Resources

Sowing information from Penn State

Sowing information from UMN

Transplanting information from Penn State

Common Crops for Community Gardens More info on Cool vs Warm crops

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