Seed Starting 102 – Homemade Mini Greenhouses

Even though for the most part starting plants from seeds is fairly easy, sometimes the seeds need a little extra pampering to get them up and growing. For example, some seeds are tiny, others might have a long germination time, or maybe the seeds themselves might be older and in need of some extra TLC. My strategy for that is to use homemade mini greenhouses, as I like to call them. It’s an easy way to increase your chances of success with problematical seeds.

homemade mini greenhouse containers

You can buy ready-made flats and containers that come with a plastic dome or lid, but I’ve had good luck making my own version. It’s less expensive that way, and if you grow plants from seed you are likely to have all the necessary ingredients you need already on hand. And of course I’m a sucker for DIY projects, especially when they save me money.

fill soil to within 1 inch of top

You can use any clean container you might have, and add your favorite seed starting soil (or soilless) mix. Fill the soil to within about an inch of the top. This leaves a little headroom for the plants after they come up. For seeds that need warm conditions to germinate, I put the containers on a heating mat that supplies bottom heat.

tomato seeds sown in coco coir

Sow your seeds and then cover to the proper depth, or leave on the surface of the soil if they need light to germinate. I often use a moistened toothpick to transfer the seeds to the soil, and it does a great job. To finish, cover the container with some clear plastic wrap and secure it with a rubber band. Give them a drink of water, and that’s all there is to it. The plastic can be removed when the seeds sprout. A cover should never be left on plants receiving direct sunlight after they have sprouted, or else the cover will act like an oven and cook the little plants!

toothpick makes good tool for transferring seeds

I typically use a 3-1/2 inch square plastic pot for this operation, since I usually have them on hand, and they are big enough for most of my needs. Last month I started petunia seeds this way. Petunia seeds are tiny, need light and warmth, and can take a couple of weeks to germinate. They’re also pricey, and I don’t want to waste a single one of them! Those seedlings are now about ready to be transplanted into larger containers.

Purple Wave petunia seedlings are ready to be transplanted

This week I started a few pepper and tomato seeds that needed some TLC treatment. My 2009 Happy Yummy Pepper seeds are losing their viability, that is if they have any left at all. These are seeds I saved from the original ‘rogue’ hot peppers, and tend to produce mostly hot pepper plants with a few sweet ones thrown in. We will see if I can get some of them to germinate. I also put some of the 2011 and 2012 saved seeds in containers too. For these pots I used 100% coco coir as the starting medium. In my experiments so far I like the way this material is performing for me, and I have had zero problems with it. It definitely seems easier to separate the roots of little seedlings grown in the coco coir, so it was a natural for this operation.

plastic wrap secured with rubber band

I also started a few tomato seeds I got from a swap with reader Jeanne. She sent me seeds she had saved from a couple of paste tomatoes she grew. The seeds from Ten Fingers of Naples are from 2008, and untested, so I thought they definitely warranted the mini greenhouse treatment. Jeanne lives in a dry climate, and says her tomato seeds regularly stay viable for 8 or 9 years. I’m lucky to get 5 years from my tomato seeds, so I will keep my fingers crossed. She also sent me seeds for Ludmilla’s Red Plum, which does better for her than Amish Paste. I am looking for O/P paste tomato varieties that do well in our climate, and these two sounded like good candidates for trial. Thanks again Jeanne for sharing your seeds.

these tomato seeds needs some TLC

I’ll be back later on with an update on how the peppers and tomatoes are doing. And that would also be a good time to talk about transplanting and thinning, which are important tasks if you grow your own plants from seed. Until then, Happy Growing from Happy Acres to all of you!

finished mini greenhouses ready for lights