It’s February, so really time to think about starting plants from seed, if not necessarily time to actually start them. (If you are itching to get going, I wrote a post a while back about which seeds to sow in February. Hint: not tomatoes.) Let’s continue with the guide, which I hope you’re finding a practical help to this complicated subject. (Parts One and Two also available.)
Choosing Seeds
If you have not already impulsively ordered a bunch of seeds without concern for whether they’re the easiest ones to grow (in which case you are a person after my own heart), now is a good time to go shopping. In most cases these days that means shopping online. You can certainly buy seeds at garden centers and even supermarkets, though they may not be on display this early, but you get a much better selection by visiting the full catalog of a seed company website.
I’ve written a post about choosing a seed catalog to order from, so won’t repeat that information here. If you are confused by the jargon used in seed catalogs, Jon Traunfeld explains it in this post.
But which plants are best for novice seed-starters to grow from seed? First of all, you shouldn’t always let ease dictate what you choose to grow. If you like a vegetable (or a flower) and want to grow it, you may be willing to take on the challenges involved. Some seeds are more cooperative than others, however. Of the many veggies that are best started indoors, here are a few I recommend for beginners:
Let’s talk more about seed-starting! Last month I posted about how to get your house ready for a seed-starting project: picking a space to use, deciding where to hang your lights, and choosing the lights. I also wrote a bit about what containers to use, but in this post I’ll give you more detail, and also talk about what “soil” (actually soilless mix or growing medium) to use.
Seedlings growing in recycled plastic egg cartons
Containers
There are basically two parts to a seed-starting apparatus: the tray, and the pot or cell. Here’s some information about each.
Trays
The purpose of a tray is to contain or capture water. You need a tray unless you want a big mess. It should not have holes in it.
Trays can be any size larger than a pot. Standard industry size is 10”x20”. You can also use takeout containers (or any food-grade plastic), old baking pans, or anything else that suits your needs.
Most trays are plastic (aside from the baking pans). Standard trays full of pots sometimes crack when lugged around and left outside, so consider doubling them up or buying the heavy-duty ones.
Pots
The purpose of a pot is to contain the medium in which a plant grows. Pots are separate entities, and cells are connected pots. You can buy cell sets that fit standard trays. You can also save the cells and pots that you bought plants in. Yogurt cups and the like are great to recycle into pots, or you can use plastic drinking cups. Plastic egg cartons can substitute for the smallest size of cell set.
Pots must have drainage. If water can’t drain out of a pot, plant roots can rot. Commercial pots will have holes already; if you use recycled items, punch holes with a nail or a knife or whatever you have (the shape doesn’t matter, but make several).
If you don’t want to buy plastic, you can spend more and get pots or cell sets made of silicone or ceramic. These should last many, many years and be easy to clean.
Any pot of the above types needs to be cleaned before each use. A 10% bleach solution is effective at killing pathogens that may lurk in bits of leftover soil. You can instead use dish soap if you’re pretty sure the pots haven’t been exposed to plant diseases.
The other type of pot/cell set on the market is the plantable kind. These are made of compressed peat, coir, or processed manure (they don’t smell!). They are filled with growing medium just like a plastic pot, but the whole thing can be put in the ground when the plant is ready.
Make very sure to keep plantable pots moist at all times, starting by soaking them before using and continuing until planting time. Remove any dry rims and some of the bottom before planting. Dryness can prevent proper plant growth.
Plantable pellets (made of peat or coir) expand when moistened and have a hole to put a seed into. They can also be planted whole, or transplanted into a bigger pot.
How big a pot to choose? It depends on how many times you want to “up-pot” or transplant into a larger container. If you start with small cells, the seedlings will have to be moved into larger pots, maybe more than once, but you are saving space, soil, and water in the early stages. (Just be sure you have room under lights for your expanded plant kingdom!) Planting directly into larger pots means you won’t have to up-pot, but you may waste time, space and materials if seeds don’t germinate, and it’s harder to keep the soil watered.
Plastic cell tray (black), silicone cell set (orange), peat pots (small), pots made of cow manure (large), compressed coir pot (single)
Growing Medium
It’s recommended to start seeds in a soilless mix consisting mostly of peat or some other organic material. There are lots of choices available on the market, and if you’re ambitious, you can mix your own. Read HGIC’s page on the topic and check out Jon Traunfeld’s post on peat-free mixes.
For smaller seeds, you want to find a finer-cut mix (lightweight and fluffy, not heavy like sand); larger seeds can tolerate a mix with larger particles. The name on the package may not mean much: “seed-starting mixes” can be quite rough in texture, and “potting mixes” vary a lot too. Look at the ingredients and try to avoid anything with “forest products,” which seems to mean little bits of wood.
Seeds themselves contain nutrients to get a baby plant started, so germination and early growth don’t require fertilizer in the growing medium. If you’re going to be growing the plant in that medium for more than a week or so, though, the mix should have fertilizer or compost in it. Alternatively, you can add fertilizer when you water. Or you can add your own compost to your growing mix, as long as it’s finished and screened, but don’t use garden soil, which may contain pathogens or weed seeds.
Next month I’ll take you through choosing what seeds to start, how to get them to germinate, and how to care for your young seedlings.
In the meanwhile, here are some more items you might consider acquiring into addition to the seeds themselves:
A seedling heat mat, especially if you are planning to start seeds for summer vegetables and flowers. Seeds need warmth to germinate, and sometimes a bit of extra heat helps.
A sprayer (for getting the soil surface wet without washing tiny seeds away) and a watering can with a narrow spout.
Clear plastic domes that fit over your trays. These help keep moisture in when seeds are germinating and plants getting started. You can buy them or improvise them out of recycled plastic clamshells (like for salad mixes).
Labels!!!
I’ll tell you more about all these helpful items next month.
By Erica Smith, Montgomery County Master Gardener. Read more posts by Erica.
Do you want to learn how to start your own seeds for garden transplants? Did you just look at the title of this post and say, wait, it’s December, why would I be thinking about this now? If your answers are ‘yes,’ then read on.
Pepper and tomato seedlings growing under LED lights, in plastic pots set respectively in a heavy-duty seed tray and an old baking pan
You begin to think about seed-starting in December rather than in March because it’s always better to hit the ground running. This is especially true if you’re new to the process. If you wait until it’s seed-starting time to start gathering your equipment and figuring out how to make it all work—and you’re also trying to prep a garden for growing—you are going to be stressed out. Spend a little time this month considering your upcoming needs (maybe even put a few items on a gift list?) and then you’ll have plenty of time to get organized.
We have a great guide to seed-starting on the HGIC website. But no guide can cover everything, and I generally find they don’t start with the absolute basics. The first question to ask isn’t “What kind of lights should I use?” or “What seeds should I start and when?” The first question is “How do I make this work in my own home?”
Location, Location, Location
Where should you set up your lights, and how much space do you need? I bet if you asked a bunch of gardeners (and their patient spouses) where seed-starting belongs, about 90% of them would say “the basement.” But of course some of us don’t have basements, and some basements are cold and damp, or are full of stuff, or are just not a place we like going. If you have a pleasant finished basement, with heating, that is not constantly occupied by teens playing video games, it may be the ideal space. But don’t begin with that assumption.
Here are some needs of a seed-starting spot to consider:
Comfortable temperature. Whatever level of heat you prefer to live in is probably fine for young plants, but you really don’t want to force them to grow in the cold. There are ways to warm them up, but why not give them what they need to begin with? Chilly basements are for storing root vegetables and wine, not for persuading tomatoes to germinate.
Access to electrical outlets. Gotta plug in those lights. Make sure you’re not going to trip a circuit breaker. Or trip over too many extension cords.
Access to water. It’s good to have a sink nearby so you don’t have to carry water too far. Also handy for washing pots and seed flats.
In sight, in mind. The more often you look at your plants, the more likely you are to catch small problems before they become large ones. Don’t hide them away in the most inaccessible corner.
Enough space. I advise beginning seed-starters to start small, but of course you’re not going to take that advice. (I mean, I didn’t.) Read the sections about lights and furniture below while you’re considering, and try not to plan for more plants than you can fit in your garden. But do remember that plants seeded into small cells may need to be transplanted into larger pots before going into the ground. Better to grab all the space you can for this project even if you don’t think you’ll use it all. You will never have enough, mwhahaha.
Protection from small friends. Make sure your seedlings aren’t going to be uprooted by curious toddlers, or chewed on by pets (you should see the elaborate fence I use to keep my cat from eating my pepper plants), or chewed on by animals that are not pets.
Protection from annoyed spouses or others who share your home. The lights will be on for at least 16 hours a day. This may or may not coincide with everyone’s sleep schedule.
There. Whatever room you are now picturing, that is the room you are going to use. Think outside the basement. You can make it work.
Plants Are Furniture
Seed-starting trays do not float in mid-air, so you’ll need something to support them. In the basement, this might be an ugly utility shelf; in the living room, you’ll want something a little more attractive. There are about a million ways to set up your growing space, and if you want to spend money, there are plenty of companies ready to sell you an entire growing system. But you can assemble the components yourself for much less. I recommend a wire shelving unit in a color that works with your décor. Or maybe you already have shelves or counters that will be perfect. Just remember three things:
You need to be able to hang (or otherwise install) lights above the plants, and they need to hang from somewhere (this is why wire shelves are great).
The distance between a light and the top of a plant should be approximately two inches. Plants will start tiny and may reach a foot tall before you scurry in a panic to find another place to put them until it’s warm enough to plant them outside. This means that either the lights need to be adjustable or the plants need to be raised up by sitting on something when they’re small. It also means the shelves need to be an appropriate distance apart (but not necessarily all the same distance; remember you can shift trays around depending on stage of growth).
Everything must be waterproof. I probably should have put this into the location section, but I didn’t want to scare you. You can put down very tasteful plastic sheeting.
Get the best lights you can afford. If you decide to give up seed-starting later on (but give it at least two years!), you can always sell them. I have switched to T5s for half of my seed-starting arrangements, and they make a huge difference in size and growth rate of seedlings.
LEDs are another possibility that is growing in popularity and availability. You don’t need the fancy blue and red ones for starting seedlings (those are for growing pot plants that need to flower); you can get white LED shoplights, which are slim and nice-looking and will do fine in the living room. They are pretty bright, so add “where they won’t shine in my eyes” to the location criteria. This is the best explanation I could find of why and how to choose LEDs.
One of the reasons I bought my LED shoplights is that they are three feet long and thus fit my three-foot wire shelving unit. Trying to make four-foot lights fit a three-foot shelf is a geometric challenge. Same with two-foot lights, which I also acquired some of along the way.
Buy a timer (the kind you use with lamps to fool burglars into thinking you’re not on vacation) and figure out how it works before you need it. Sixteen hours a day is minimum for healthy seedlings.
Other items for your list: a power strip, and hooks and chains to hang the lights as needed.
If you want even more detailed information about growing under lights, this podcast episode is useful.
Wire shelving unit with hanging lights. This was in the geometric challenge days, fitting four-foot and two-foot lights into a three-foot shelf.
Buy More Takeout
You will need to start your plants in something. More on that in a later post, but for now you might want to be saving your plastic takeout containers (rectangular is more efficient than round), yogurt pots, and salad clamshells. Or you can browse some good garden supply catalogs and websites to see what’s available. It may be possible to get away from plastic altogether (I’m trying) but not in a cheap or practical way yet, so focus on reuse and/or durability. Hint: if you feel you might be committed to this hobby, and you want standard-size seed-starting trays (usually 10”x20”), find the heavy-duty plastic ones that will last decades with care, rather than the cheap kind that crack after a couple of years of use. I asked for the former as a Christmas gift a few years ago (much better than perfume!). But I also know exactly how many pots of all the different volumes fit into a black rectangle that once held moo shu pork. Mini-trays like that also arrange themselves more flexibly under lights than large trays.
Seedling pots nestled into plastic takeout containers and styrofoam mushroom containers
Let’s pick this discussion up in January! Meanwhile, start browsing those seed catalogs.
By Erica Smith, Montgomery County Master Gardener. Read more posts by Erica.
Every year I warn fellow gardeners not to rush on getting seeds into pots for warm-weather vegetables. Tomatoes, in particular, outgrow their indoor space under lights much faster than you’d think, but you can make this mistake with many plants that shouldn’t go outdoors until the chance of frost is past and the soil temperature is at least 60 degrees F. There’s often a several-week gap between the average-last-frost day that you used to count back from when calculating start dates and the actual day that it’s safe to put the plants in the garden. That can go either way, of course, but unless you’re inclined toward taking risks, it’s better to err on the side of later planting. The seedlings will grow faster under warm conditions and catch up with their early-planted peers.
So, there was no reason to put the pepper seeds in as early as the very end of February, but I did it anyway. We all have those moments. Mid-March would have been fine, but I know I was feeling anxious about other things and probably projected those feelings onto my peppers. And now I have some large strong well-grown pepper plants that are more than ready to go into the ground–which some of them are going to do this week, soil temperatures notwithstanding.
Some of my large pepper plants hardening off, guarded from inside by a helpful cat
If you have been in this situation, which most of us seed-starters have, here are some things you can do, more or less in chronological order. This applies also to plants you may have bought a while before you could plant them–we all do that too!
Sunshine, increasing temperatures, warm rain showers, and the return of migratory birds are all signs that Spring is getting closer. They are all reasons to be excited about Spring and all the possibilities that the new gardening season will hold.
It’s always tempting to go out and start sowing seeds at the first glimpse of sunshine, but most seasoned gardeners know that patience is the best policy. It takes several weeks of warm air temperatures and sunshine for the soil temperature to get warm enough to signal the seeds to germinate. Mother nature provides mechanisms to protect seeds from germinating too early (called “seed dormancy”) and there are certain requirements that must be met before sprouting occurs.
Did you know that every seed has an optimum range of soil temperatures for germination? This factor helps determine which seeds are cool-season versus warm-season. Penn State Extension has a great article regarding Soil Temperature and Seed Germination that you should spend a few minutes reading.
I started my tomato seeds only yesterday, and no, that is not an April Fool’s joke. That is a goal achieved: resisting temptation to get going too early. Getting out of March tomato-free. I finally did it!
In mid-February, I started my Gypsy, Monty, and Green Magic broccoli, Snow Crown cauliflower, Lacinato kale, several types of lettuce, and some Big Blue salvia.
Italian flat-leaf parsley was started in mid-January. Most of these transplants will be planted in the garden or containers in the first week of April after hardening off for at least a week in my cold frame. My pre-sprouted snap peas will be planted in late March. Planting dates for central Maryland can be found here on the Home and Garden Information Center website.
In early March, I will be making a trip into Baltimore to get some other seeds for Sugar Ann snap peas, Jade string beans, and a couple of other things. In late March, I will be planting some seed potatoes in containers, just to see what the yield is. On March 27th, seven to eight weeks before the spring plant out date of mid-May, I will be planting Galine eggplant and several different types of peppers.
In previous years, I’ve planted tomatoes six weeks prior to my plant out date, but they have been leggy. This year, I’m planting them on April 10 for planting in the garden and containers on May 15.
My latest soil test, done in May of 2019, says to incorporate one pound of nitrogen (N) per 1,000 square feet. Only N is required since the beds contain the optimum amount of phosphorus (P) and potassium (K) and are at the correct pH.
To determine what fertilizer needs to be added to my beds which are 32 or 40 square feet, I will have to convert this recommendation to determine the amount of urea (46-0-0) to apply to my beds. This is fairly simple to do, using the following equation. Amount of N/.46 (% of N in urea) x beds size/1000 square feet. This yields the following: 2.17 pounds of urea x 0.032 for a 32 square foot bed equals .069 pounds of urea or 1.1 ounces. I guess I’ll have to get out my kitchen scale.
Alternatively, the University of Delaware suggested 2.5 pounds per 1000 square feet or 2.5 x .032 = 1.28 ounces of urea. This calculation works for almost all recommendations from soil test labs. However, if in doubt, you can always Ask a Gardening Expert at HGIC.
By Kent Phillips, University of Maryland Extension, Howard County Master Gardener
