Everybody is into seed starting this spring because of renewed interest in gardening and there are tips and tricks to this great money saving hobby. New gardeners frequently think that you just throw some seeds from a seed packet into potting soil and place them in a bright window and hope for the best. But there are much better methods for becoming a successful transplant grower with a few inexpensive pieces of equipment.
For a tour of my greenhouse where I start hundreds of seedlings a year, check out this video.
Choosing Your Perfect Seeds
Seed starting in spring is a rite of passage for me. Fingering all the seed packets, shaking them, and admiring the beautiful covers is all part of the process. If I don’t have at least a hundred seed packets stacked up, I get restless and start browsing more seed catalogs.
The selections are dizzying in the varieties and take a look at the prices! Five and six dollars for some seed packets. So, choose with care. Sometimes it is easier to buy transplants in the spring instead of messing around with seed starting. But if you want unusual or different varieties, start them from seed. Also, if you want a ton of something, like 1000 Zinnias, start those from seed as the individual transplants can add up. Think about this as well; the more seeds you start, the more space you need in a usually limited lighted area in your home. Even if you have a greenhouse like I do, there is limited space.
Seeds are plant package miracles that contain an embryo, nutrition, and the seed coat that given the right conditions will produce a plant identical to the parent (except for hybrids). Miniature plants are in those seed packets! For great information on selecting the best seeds or ‘shopping’ the seed catalogs, go to The National Garden Bureau for an excellent rundown on seed facts. But you need to decide when you jump into seed starting, your budget for equipment and your time.
For this year, I would order sooner rather than later. After browsing seed company websites, many are already out of stock of many varieties. So, if you haven’t ordered already, do it soon.
It is All About Timing
Before you even pop that seed into a peat pot, know the optimal germination temperature of the soil, light required, and stratification if necessary. Stratification just means breaking dormancy of the seeds with cold temperatures, sort of like mimicking outdoor conditions. I do this by placing my seeds in the refrigerator.
A lot to think of before you even plant, google each seed type to see what its requirements are as it can vary. For example, don’t cover seeds of primulas or begonias as they require light to germinate. Pressing the seed into the seed starting mixture will give the seed good soil contact, a requirement for germination.
And everyone wants to know when to start your seeds. Start too early, and the plants will get large and root bound, and too late, and you have tiny tender seedlings to place out and they might not make it. Go to A Way to Garden for a handy reference where you can plug in your frost free date and it calculates exactly when you should be starting your seeds. A valuable reference that has saved me a lot of time figuring dates in my head, you can customize it to your area.
Here are the Reasons I Start Seeds
1. More Choices-At a nursery they might sell 20-25 varieties of tomatoes. From seed you can grow at least a thousand more. Some flower varieties like Nigella, Love-in-a-mist, or annual Poppies must be started from seed outside to be successful. See my post on Annuals that Rock!
2. Save Money on Plants
A packet of Zinnias will set you back by $2.50 to $4. If you bought all those packs of annuals at the nursery that one packet can start, you pay that many times over. Plus, if you grow heirlooms, you can save the seeds and regrow every year.
3. It’s Easy
Most vegetables should be started directly into the garden. Planting transplants of cucs, beans, peas, beets, carrots, lettuce……. the list goes on, is expensive and time consuming, and not practical. Starting seed directly into a vegetable garden avoids transplant shock and gives veggies a head start.
4. Save the Bees
Many transplants have been treated with insecticides that negatively impact bee visits. Some nurseries are careful and transparent, but some are not, and many times aren’t labeled with the insecticide treatment. Go to my post on Pesticide Free Nurseries. You are controlling your quality of new transplants by starting them yourself.
5. It’s Fun!
Reconnect with nature during the dark days of winter and watch your seedlings grow! Make it a kid project! I love watching the snow pile up outside while my healthy seedlings are growing before my eyes inside.
Right Conditions & Equipment
Your job when planting a seed is to provide the right conditions for germinating and growing on to be ready to transplant into your garden. Here’s a rundown on some handy equipment that will make your seed starting journey a whole lot easier.
My most important piece of equipment is a PVC light stand for my grow lights. Go to PVC Light Stand for easy to follow, inexpensive directions for a light stand. I put this together myself, so anyone can construct one. Yes, you can use your window sills for light, but a light hung a few inches above seedlings is vastly superior and will make your seedlings fat and happy, not thin and spindly. There are too many cloudy winter days for seedlings to get their required allotment of light. I just use a simple LED shop light, available at any hardware store. LED is the key word here, as it gives off a much stronger light than fluorescent.
Most seeds benefit from bottom heat and will germinate much quicker. You could use a radiator or other warm surface, but I like the heat mat as it fits exactly under a flat and you can control the temperature. Inexpensive also, heat mats are available on Amazon. Be sure to remove the germination mat when the seedlings start to pop up, especially if you have a clear hood on top to create a moist environment. You don’t want the seedlings to bake!
Flats are simply low shallow plastic trays with drainage that you can fill with soilless medium. Once filled, I nest the flat into another waterproof tray to catch any excess water. Some trays are divided into cells, so you are growing a seedling in its own contained root run making it easier to transplant to a larger one.
Damping Off is the number one reason for seedling failure. The seeds germinate and then just melt away. A fungal disease spread by spores, you want to keep everything – soil, containers, trays- very clean. Wash containers with a dilute bleach solution and use sterile soil.
Damping Off thrives in warm and moist conditions, so you need good air circulation. I use a small fan attached to my light stand to move the air to discourage “damping off”. And it works. Simple solution, but effective. Just be sure not to over saturate your soil as that is the most common cause of seedling failure. For my greenhouse, I have a heftier fan to circulate the air.
Another way to stave off damping off is to use some anti-fungal spices like cinnamon, turmeric, and cayenne sprinkled on top. Or water your plants with a tea made out of one or a combination of these spices.
I like to water with a mister, as it disturbs the seedlings the least. But it requires a lot of time to mist all my seedlings by hand, so I have graduated to a larger Dramm watering can with a fine mesh “rose”. A “rose” just diffuses the water so it falls gently onto the seedlings and is much more efficient than a mister.
Another watering choice is to simply buy a simple gallon sprayer at a big box store and fill it with water for a gentle rain.
Additional Lighting Units
The LED grow lights are wonderful, but sometimes every seedling won’t fit under the grow light. So, I supplement with LED spray lights.
You need a source of sterile soilless medium to start your seeds. I use concentrated soil blocks as I don’t want to lug home large heavy bags. Much less expensive and more convenient, you can find these compressed bricks online or at Home Depot, or other hardware stores. There is no nutrition in this soil medium, so as soon as your seedlings are up and running, you need to fertilize. Another soil that I use is Pro-Mix, a peat-based mix with lots of perlite added so it won’t compact and incorporates lots of oxygen to the new seedlings.
Seed Starting Containers Options-There Are So Many!
An easy and cheap way of starting your seedlings or to transplant all those little seedlings is to create small biodegradable pots out of newspaper. If I have newspaper hanging around, I try to use it up. Simply fold your newspaper into strips, roll around a water glass the size you want to create, and tie with twine. Tucking in flaps at the bottom creates a snug little container to start seedlings.
Another sustainable option is to use CowPots.
Cowpots is a family owned American company that are peat and plastic free made from recycled, renewable composted cow manure. CowPots are 100% biodegradable and they don’t smell! That means, there is nothing to throw away. Here is my friend Amanda who helps run the family farm in Connecticut describe them.
CowPots have a suggested shelf life of approximately 12 – 16 weeks. The natural aspect of manure allows for even the smallest root to penetrate, so when it’s time to transplant, you never crush or tear the pot wall, leaving the tender roots intact. CowPots continue to benefit your plant and soil as they decompose in the garden. Coming in all shapes and configurations, these are my go-to for transplants of all sizes.
I lose seedlings every year for a variety of reasons. The most likely cause or seedling failure is over-watering. Be prudent with your watering and don’t over-saturate your soil.
For Winter Sowing of seeds which is a easy method to start seeds outside without special equipment, go to my previous post.
For a great resource, I use this comprehensive seed starting reference by my friend Julie Thompson-Adolf. If you wonder if your seeds need light or not, stratification (pre-chilling), or any other special requirements, there is an appendix with many seed varieties listed. You will be a much more successful seed starter!
6 Replies to “Secrets of Great Seed Starting for Experts and Beginners”
awesome article, great pics! Can I share with my Hort students (and I will urge them to sign up for your newsletter/blog)
Of course. I welcome all students of horticulture!
Good article. Can you tell me where you purchased the spray lights? I tried looking online but only found decorator type lights. Thank you.