When I first started gardening, I had a tough time figuring out what plants I should start in my greenhouse, which plants I should direct seed, and which plants I should let seed themselves. As with most gardening and permaculture questions, the answer is……..it depends.
Before we even get into which plants I like to start inside, which plants I like to direct seed, and which plants I like to let self-seed, I think it is important to understand the benefits and drawbacks of both methods of propagation.
Benefits of Direct Seeding (Also the Drawbacks of Starting Seed Indoors)
– The plant, never having moved, will have a stronger root system, than plants that have to deal with transplant shock.
– Direct seeding is cheaper than starting seed indoors. No need to have a heated greenhouse and no need to buy expensive potting soil.
– Direct seeding is less labor intensive than starting seed inside. No need to harden off your seedlings, or dig holes to plant your starts.
Drawbacks of Direct Seeding (Also the Benefits of Starting Seed Indoors)
– You run the risk with frost sensitive plants, that if you plant too early then they could get bitten by a late season frost.
– Warm season plants will be just germinating, when already started plants are already established. This allows for more production earlier in the season from plants started inside.
– You have more weed competition when direct seeding.
Benefits of Self-Seeding Annuals
– There is no work required to just let the plants seed themselves.
– They are quick to germinate in Spring, and you do not have to worry about transplant shock.
– The seed is free, and the strongest plants will survive.
Drawbacks of Self-Seeding Annuals
– The seed will not necessarily be pure. It may have cross-pollinated with other plants from it's family.
– If you like to rotate crops like I do, then this is a problem because the seed will germinate very close to where the plant was the year before.
Having said all that, I personally prefer direct seeding for most plants. I think you end up with stronger plants when direct seeding, and the labor savings is enormous. However, there are a couple of plants that I do like to start indoors, and a couple of plants I like to let self-seed.
Plants That I Like to Start Indoors
- Broccoli & Cauliflower
Plants That I Like to Let Self-Seed
- Lettuce in the late summer, so I can harvest as a fall crop.
- Basil in the late summer, so the seed can overwinter, then emerge in the spring.
- Volunteers – I will occasionally let just about any plant self-seed. If I like the result, I will let the plant carry on, if I don't I will remove it, or thin it out.
An Update From Last Season
Last year I did not have stellar results starting plants in my greenhouse. We had a very cool spring, so the soil temperatures had not gotten warm enough in the pots, and I probably kept the nighttime thermostat too low for my warm season plants. Anyway, this led to an accidental experiment in regard to starting seed indoors versus direct seeding versus allowing annuals to self-seed.
It took about 2 months to finally start to get germination of my tomato plants. I thought maybe I had a problem with the seed, so I direct seeded some tomatoes, and I had some tomatoes coming up as volunteers from last season.
My direct seeded tomatoes came up very rapidly, and were bitten by a late frost, so they are stunted and will be removed. This is the danger of direct seeding warm season plants too early.
Direct Seeded Tomatoes Bitten by Frost
My greenhouse tomatoes that did germinate looked really nice.
(The wilted tomatoes laying on the soil are ones I thinned out of the pots, as I grow (3) per pot then choose the best one.)
What is really interesting is my volunteers outperformed both my direct seeded tomatoes and my greenhouse transplants. Starting out, they were only slightly smaller than my best greenhouse transplants, and they didn't have to worry about transplant shock. Another variable is that my volunteers were in a sheltered area that did not get frost, so that certainly helped, but they were still way ahead of my direct seeded plants even before the frost.
This volunteer tomato couldn't have found a better place, as it is nestled up against an oregano plant which is a great companion for tomatoes.
The conclusion here is Mother Nature knows what she’s doing. Typically, seeds fall to the ground in fall, and over winter. Then in the spring they jump out of the ground well ahead of anything we plant in the spring. We should direct seed some of our cool season plants in the late fall. I bet we would get earlier production with a higher volume, while avoiding many of the common pests.
~ Phil Williams
Phil Williams is a permaculture consultant and designer and creator of the website foodproduction101.com. His website provides useful, timely information for the experienced or beginning gardener, landscaper, or permaculturalist. Phil's personal goals are to build soil, restore and regenerate degraded landscapes, grow and raise an abundance of healthy food of great variety, design and install resilient permaculture gardens in the most efficient manner possible, and teach others along the way.