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Sowing Seeds: Seed Sowing and Planting Outdoors

Seed Sowing and Planting Outdoors

Photo courtesy of Flickr cc/Chrisseee
Photo courtesy of Flickr cc/Chrisseee

In the spring, it's time to get out in the garden and plant the rest of your vegetables, annuals, and perennials. Peas, early lettuce and other early crops and vegetables should already be well underway. But in May, after the last frost, start thinking about planting out warm-season vegetables and tender annuals and perennials. Here are a few tips on seed sowing and planting out your summer bounty.

Sowing Seeds: 

When sowing seeds, it's important to prepare the soil ahead of time. In the fall or spring amend the soil with compost or composted manure.  Dig it in! The soil should be forked over 6 to 8 inches deep. If you are starting a new vegetable patch, wait a week after you have turned the soil to plant. This will allow weed seeds to germinate, which can be hoed out of the bed before you plant.

Read the package for specific planting directions, but the general rule for planting seeds is at a depth 2 to 3 times the diameter. Plant your seeds in small furrows that can be made with the edge of a hoe, a stick or your finger. Your vegetable rows should run north to south to give the plants equal exposure to the sun. The rows should be far enough apart to allow space for the full grown plants. If you are planning to walk through the rows, leave an additional 12 to 24 inches for a path.

Space the seeds evenly when you plant them in the furrow. One easy technique is to crease one side of the seed packet and slowly shake the seeds out of the V that is formed. Another is to find an old salt shaker that has large enough holes for the seed to spill through. You will have to thin the seedlings regardless of how carefully you plant. It is better to start off with too many than too few in case some of the seeds do not germinate.

Cover seeds, lightly tap down on the soil to ensure good seed-soil contact and gently water them in. If there is no rainfall, check to see if they need water on a daily basis - the soil should stay damp (not wet).  Water with a watering can that has a rose (a head to it) until they germinate. Gently swing the watering can from side-to-side to make sure the falling water does not displace the seeds. Sprinklers are fine once the garden is established, but not during the initial stages when tiny seeds are lying just below the soil surface.

  • Sow cold-weather crops such as radish, lettuce, spinach, peas and broccoli as soon as the soil is workable in late March to early April.
  • Sow warm-weather crops such as cucumbers, beans, pumpkin and squash directly into the garden in May.  For pumpkins, squash and cucumbers, build a small mound of soil (12 to 24 inches wide and 4 to 6 inches high) and plant 3 to 5 seeds per mound. Thin as necessary.
  • When sowing annual flowers, mark out the area you are planting.  When planting annuals from seed plant them in large patches or drifts not in sharp rectangular and square shapes. Rolling drifts that blend into each other create an impression at a distance and are pleasing to the eye.
  • Once you have marked off a planting area, sow the annuals in rows 6 to 12 inches apart (the seed package will indicate the correct spacing for the plant).  Sowing the seed in rows allows you to discriminate between early seedlings and weeds. Thin seedlings to create a uniform mass.
Sow cold weather crops, like broccoli, as soon as the soil is workable in March or April
Sow cold weather crops, like broccoli, as soon as the soil is workable in March or April

Planting Out:

It is important to prepare the soil ahead of time when planting out young seedlings and perennials. Amend your soil by adding compost or composted manure and forking it over. Rake the soil to smooth it out. Sprinkle fertilizer according to the directions on the package. Look for organic, granular fertilizer with low numbers that will slowly break down in the garden. Scratch it in with a rake. Dig your hole and you are ready to plant.

  • Harden off tomato, eggplant, and pepper transplants before planting them out after the last chance of frost. Harden off by placing the plants outside during the day and inside during the cool night. Avoid placing the new seedlings in intense sunlight or in a windy location - they need to gradually acclimate to the outdoors.
  • When planting tomatoes, wrap a small piece of glossy magazine paper around the base of each plant and cover the bottom edge of the magazine with soil to keep it in place. This will prevent cutworms from gnawing at the young stems of the plants.
  • Mulch your vegetable beds once they are planted. Add an extra layer of compost around your tomatoes. Mulch rows by laying down newspaper and covering It with straw.  Remember to wet the newspaper before you lay the straw down and wet the straw so that it does not blow all over the yard. Mulch will minimize weeding and retain moisture. If you apply straw mulch around your zucchinis, squash, pumpkins and melons, your vegetables will have a dry surface to grown on.
  • Whether planting annuals or perennials, make sure that the store bought container is well watered (water the day before planting) before placing the plant into the ground. This will ensure that the root system has ample water during the planting process. Then water again, once the plant is in the ground.
  • When planting vegetables, annuals or perennials make sure to observe proper spacing. If the plants are too crowded then you will increase the risk of pest and disease problems later in the season once they fill out.
  • Stagger the rows when you plant so that the plants have optimal light conditions. The easiest way to do this is to plant one row and then shift the spacing of the plants in the following row so that they are positioned in between the gaps of the first row. The plants will then be laid out in a triangle formation rather than ending up perpendicular to each other.
  • Fertilize annuals when you plant them. Follow up with an additional feeding of water soluble fertilizer in July, following directions on the package. Annuals complete their life cycle in a single season and tend to be heavy feeders. Do not over-fertilize. Many fertilizers are high in nitrogen and too much will promote leafy growth with few flowers.
  • Some tropical plants and heavy feeders will need a more consistent fertilization over the course of the summer. Brugmansia (angel's trumpet) and Hibiscus (tropical hibiscus) get fed on a fortnightly, and sometimes weekly, basis in this garden with a diluted liquid fertilizer.
Harden off tomato plants before planting them out; photo by Ivo Vermeulen
Harden off tomato plants before planting them out; photo by Ivo Vermeulen

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