Time to plant some seeds...
For those of you planting from seed, now is the time. I say "now" in the broadest sense because every seed is a little different. You really want to take the time to read up on the growth time for each of your seeds. Some (like tomatoes) will say to plant 6-8 weeks before outdoor transport. Others (like lettuce or spinach) are more in the 4-6 week range. I plant beans no more than 2 weeks before outside planting because of their fast growth rate.Outdoor planting time for me is mid-May. That’s about a week past the local frost date, which I feel is pretty safe. It also allows me to acclimate my seedlings to outdoor life (but more on that later).
There are tons of seed-starting kits out there; from small 10-seedling trays to big 72-seedling trays. If you’re growing from seeds for the first time, I’d recommend a smaller tray. I use a few different sizes made by JIFFY, which has a couple nice features.
First, the trays have a transparent lid. All seed trays should have this, but if you find one that doesn’t, don’t buy it. The lid helps keep in moisture and warmth during germination. It’s less important once the seedlings get a few inches tall, but it is crucial for those first few weeks. Essentially, it's creates a mini-greenhouse.
Seed starter tray with irrigation channels in the lower tray. |
Second, the trays have an irrigation channel built into the base. It’s a huge help in making sure everything is evenly watered. While you can water every peat pellet independently (not a bad idea until your seedlings germinate anyway), an irrigation channel cuts down on time tremendously as well as prevents one pellet from drying out while another is sopping wet.
Third, the trays come pre-filled with peat pellets for starting your seeds. I have seen a few trays that do not have pellets (which you have to buy separately). This is a waste of money, and for a few bucks you can get a stocked tray. You can save your tray from year to year, but the cost of a box of replacement peat pellets is about the same as a new, fully stocked tray. For the hassle of storing your seed tray year round it’s almost worth it to just buy a new one each year.
Last, the trays I get fit my needs. I have a 72-pellet tray, a 36-pellet tray, and three 12-pellet trays. They fit my needs and my available growing space. It’s a good idea to plant a few more seeds than you actually need since no one actually gets 100% germination. However, if you only need 20 plants, then don’t plant 50.
Science Time!
Why are we planting seeds in peat instead of dirt? Aren't they the same thing?Peat. Very useful. Not terribly pretty. |
Normally, decomposition is responsible for returning nutrients to the soil. The acidity of bogs prevents this and plant matter simply accumulates. Over the years, this accumulation can become extremely dense and peat is born. Since decomposition is suspended, peat retains much of the biological carbon and nutrients it normally would have released into the soil. If left alone (for a very long time) peat eventually becomes coal.
Peat is used for many purposes, but it is commonly used as a fuel source. Like coal, peat burns very well and is classified as a slowly-renewable bio-fuel in much of the world. Big users of peat are Finland and Russia, both of which own extensive peat bogs. Sadly, extensive bog-mining and draining have caused massive ecosystem damage. As thousands of years of carbon detritus are exposed to the air, CO2 is released and becomes a contributor to global warming. Fortunately, peat used for small scale agriculture (like your seed starter trays) can be produced in a factory without damaging the environment.
What does peat mean to you, the gardener?
Peat is great for starting seeds. Its organic nature means it holds moisture well. However it also drains very well. Peat tends to prevent the soil from getting too wet. Adding peat to dirt makes it "fluffy". It allows for better drainage, and it contributes nutrients to the soil as it decomposes.
Seeds love peat pellets for exactly this reason. You don't want waterlogged seeds. Peat pellets help keeps seeds moist while preventing them from drowning. Topsoil is great for mature plants, but will often kill off seedlings. Also, peat lacks many of the dangerous microbes and fungi that soil has. Seedlings are extremely fragile, so mold and bacteria can be huge threats to them as they are sprouting.
Starting your seed trays.
Each tray should come with instructions. It’s not a bad idea to read them.That said, here’s a couple tips to prepping your trays:
- Use warm water.
- For a tray of 12-pellets, I use ½ to 1 cup of water. This varies a little by pellet size.
- Add water as evenly as possible.
- Walk away for an hour.
This does not mean they are defective!
This does not mean they need more water!!! (Notice the extra exclamation points?)
Hydrated peat pellets. String is used to divide seed types. Pellets on the right have the mesh wrapping pulled back. |
All it means is that they need time. If you put in more water, guess what? They will absorb it. All of it, until you have little soggy messes of peat unfit for seed starting. If you give them time, they will absorb all water they need and will swell up. If, after you wait, a couple still look a little dry and/or stunted, gently give them a little extra water and wait again. Remember seeds like moisture, but they don't want to drown.
Next, you want to do a little prep work before planting your seeds:
- Plan out how many pellets you will dedicate to each seed type you have. Eventually, 1 pellet = 1 plant.
- Mark your plan on your tray in some way. I use string to create easy dividers and I label each section. It is very easy to mix up pellets once they are planted.
- Prepare your peat pellets by peeling back the mesh around the top. Don't remove it entirely; the mesh keeps the pellet from falling apart.
- Make 2-3 indentations in each pellet. I use the blunt end of a paintbrush. You will need to read your seed instructions to determine how deep of a hole you need.
- Use a small dish to pour out one type of seed. Do NOT work with multiple types of seeds at a time or you will confuse yourself.
- Place one seed into each hole you previously made in your peat pellets. This means you will have 2-3 seeds per pellet. Don't worry; we'll thin these out once they start to grow.
- Gently cover the seeds with peat. Do NOT pack them down harshly.
- Once you have finished working with one type of seed, repeat steps 5-7 with each type.
- When you are finished, cover your tray with the transparent lid and place in an area away from cold windows and direct sunlight.
Science Time! (Last one for this post, I promise)
What is a seed, and what makes seeds germinate?
Seeds are miniature dormant plants, covered by a durable shell. Inside the seed, they have a tiny food supply and are effectively in suspended animation (How Sci-Fi!) until the ideal conditions are met.The "ideal conditions" are slightly different for every plant, but for most of what goes in your garden, the basics are: Moisture is present and the temperature is conducive to growing.
How can seeds tell it's OK to germinate?
For most seeds, the seed coat (the hard outer layer) is semi-permeable. That means light, temperature, air, and moisture can get to the plant embryo inside the seed. When the plant embryo is exposed to these ideal conditions, it begins to grow.Some seeds have an impermeable coat that has to be breached before it will germinate. Breaching the seed coat can happen in a number of ways. This includes frost action (frost formation physically cracks the coat), fire (heat cracks the seed coat open), and biological action (bacteria or the digestive tract of animals breaks down the seed coat). These are different strategies employed by plants to ensure that their seeds germinate only at certain times.
Some seeds even need to be exposed to cold temperatures followed by a warm-up before germination will happen. In this case, plants have evolved in such a way as to detect the passing of winter. If the seed does not experience cold temperatures, it assumes that winter has not come yet and will not germinate, even if every other condition is met. This is most commonly seen in bulb plants like tulips, hyacinths, and daffodils. Botanists use "cold stratification" to trigger these cold sensitive plants to germinate. By placing bulbs or damp seeds in a refrigerated space for a month, the seeds can be "tricked" into thinking that winter has come and gone.
What does light have to do with germination?
Seeds want to be in soil in order to germinate successfully. In nature, seeds get buried by the elements, animal actions, and by being covered in falling plant matter. A seed exposed to full sunlight assumes that it is not buried and often will not germinate.Likewise, a seed does not want to be buried too deeply. A seedling can only break through so much soil before its resources are exhausted. Thus, seeds do not want to be exposed to 100% darkness. They assume that they are buried too deep and will not germinate.
This is not a fixed rule, mind you. Out of 100 seeds you will always get a couple to germinate whether they are planted 2 feet down or not at all. What I'm saying is for the highest germination rate, you want to bury your seeds around ½ inch down, with loose soil or peat on top. This will give them enough covering to retain moisture and block sunlight, but will not be so deep as to kill them off.
Some final tips to planting your seeds:
- If your peat pellets get too wet, pour off the excess water and let them dry out for a day.
- Some seeds (like peas and beans) like being exposed to a little water before being planted. Soak them in a bowl for a few hours (or overnight) before planting. After the soak, look and see which have swelled up. If a pea swells up from the water, it's good to be planted. If it doesn't, it might be a dead seed.
- Some seeds have a very hard seed coat, which hinders germination. My best example is the Castor Bean plant. You can use a nail file to gently scrape away a tiny portion of the seed coat to allow moisture to penetrate. Don't file too deeply, though, as you can injure and kill the plant embryo within.
- A good rule of thumb is plant your seeds at a depth equal to their size. Very small seeds need shallow planting. Larger seeds like to be a bit deeper.
- For tiny seeds, use tweezers. Can't recommend this enough.
- Keep your seeds away from the cold. If you're starting seeds indoors it's probably because it's too cold outside. Be cautious of windows as these are often the colder areas of a house. Use a heating pad on its lowest setting if a boost of warmth is needed.
- Don't let your peat pellets dry out. Water them regularly. A spray bottle works wonders.
- Don't let your pellets get soggy. Avoid over-watering. Again, a spray bottle works wonders.
- If you have seeds with very different preferences (lettuce and spinach love moisture, but basil and tomatoes do not) consider planting them in separate containers, not just different sides of the same tray. That way you can water them without fear of ruining one group or the other.