January 12, 2011

It is (Was) Time To Start Tomatoes (In Coastal Texas)

The average frost free date in my garden is March 15. For the first spring planting I find starting my Solanaceae seeds 12 weeks in advance works best. I've seen garden guides that instruct you to start your tomatoes 8, 6, or 4 weeks before the last frost. 8 weeks would work, 6 weeks is cutting it very close in my opinion and you'd have small plants. But 4 weeks! That is unreasonable. 

Giant peat pellets, compressed and inflated
(Later on in the season when there is more warmth and more sun the seedlings grow faster and therefor the time they need to grow for transplant is shorter.)

But back to December... counting back 12 weeks from March 15 we get December 15 as the first seed starting date for tomatoes, eggplants, and peppers! Of course I'm late this year (another good reason to aim for 12 weeks, that way even if you end up with 8 weeks you're still going to have nice sized plants for spring). I like to start mine 12 weeks early for two reasons. One, I have larger plants to put in the ground and with tomatoes, a larger plant means more stem to bury and more buried stem means more roots. Larger pepper transplants mean that I'm eating stuffed jalapenos earlier. The second reason is that, while Mar 15 is our average frost free date, some years we have very mild winters and I can put the tomatoes in March 1 easily or even as early as February with frost protection. If I have sizable plants I have more flexibility because they're less sensitive to cold.

In the past I've used peat pellets, peat pots, and standard black plastic cell packs of various sizes. Some years I grew thousands of plants in a greenhouse, others I only had a few so I kept them inside, and other years I started seedlings under lights. 

Greenhouses can be tricky in our climate and I have a small one which is harder to use than a big one. Here it is not unusual to have a 35 degree plus difference between high and low. Unless you have a large volume of air plus a significant thermal mass to help regulate temperature fluctuations you end up running out there all day long to ventilate or to close up the ventilation and it can't stay warm through the night without supplemental heat. Seeds require consistent temperatures for germination - large fluctuations prevent germination. This year I'm planning some projects to make the greenhouse more useful, but that is another story.

So here is how I start seeds:

First I stir up my seed starting mix in a bucket. I would generally recommend a commercial soil-less seed starting mix. They're made mostly of peat or coir and that can help prevent some of the soil born issues (like damp-off) you might have. Of course always buy organic or avoid anything that has time release chemical fertilizers in it. I can't get soil-less seed starting mix locally, I don't have any left over, and I didn't feel like driving into Houston or getting it shipped so I'm making my own mix using a reasonable potting soil blend from the feed store. This is not the best option but I've had a lot of practice so I can mostly make up for this soil's deficiencies of character.   

 Into the potting soil I mix some amendments. Once again I used what was available, in this case vermiculite (left) to lighten the soil and give it macro-pores and a premixed organic granular fertilizer (below right) made up of kelp meal, humates, dried molasses, poultry manure, and greensand (glauconite). I also add a little bone meal. You should definitely not add too much fertilizer. Too much fertilizer causes mold and fungus growth, unhealthy plants, and rotting seeds and soil (eww). However, since I grow my plants to a good size before I put them in the ground they need some kind of food. They can't grow for 12 weeks without something to eat.

 I mix all this up in the bucket and get it damp. Not too wet or it will compact and not too dry or it won't be one continuous mass and water won't move through the soil column in the cells. Once it's damp I scoop it into my seed trays.


*A note on trays. These are 1020 flats (without holes) holding 6, 6-packs. I order them by the case but you can often get them or something similar in small quantities from your local garden center and or a good nursery that caters to gardeners (as opposed to landscapers).

As you can see from the picture above, the soil is roughly scooped in there all the way to the top. I give it a shake to level it out a bit and then I take 3 or 4 of the 6 packs (nested so they're more rigid) and I give each of the packs in the tray a good press to firm up to soil. This way I know that the whole body of soil from top to bottom is one cohesive unit and when I water, from above or below, it will become evenly moist.

We end up with this (left). Next step is to put the seeds in the flats (make sure your hands are very dry). I tend to put two or three in each cell. Seed is relatively cheap and I don't want to waste time and have to start over because I put only one seed per cell and later found out the germination was poor. The size of the seed determines how you proceed. If the seed is very small or needs light to germinate I won't cover it. If the seed is larger (like a tomato or brassica seed) I gently sprinkle some soil on top and tamp it down just a bit. If it's buried too deeply it will take a long long time to germinate (or won't grow at all). If it's right on top with no covering you may get germination or you may not but you will have a hell of a time keeping it moist enough. 

Then I water. Often I water from below. If you water from above you must be very gentle or the seeds get dislodged and either float (and now they're not covered) or sift down through your soil and become buried too deeply. If I feel like my soil isn't quite moist enough to begin with and if the seeds are large enough I'll do a gentle brief top watering just to make sure the zone where the seeds are is damp. But normally I fill the tray a quarter to half full of water with the cell packs sitting in it. Especially with the first watering, the cells will often wick the water up in a blink. You can gently touch the top of the soil to see if the water is making it to the top. If it feels too dry and the water is all gone in the tray then add a little more. Most of the time I end up with a small amount of extra water in the tray. That's fine - as the cells dry out they'll suck water from below. But, you don't want them sitting in too much water or things will be soggy. If seeds stay soggy for too long they start to rot and if your plants have roots, they'll suffocate.

Label!!! (I would type that word in a flashing neon font if I could) It seems like you'll remember what you planted, especially if you write it down on some paper, even if you only have one kind of seed. But you won't. Ask my how I know :-) 

I record the name of the plant on the front of the popsicle stick and the date it was seeded on the back (just month and day... most of the time I know what year it is). I normally just list the variety rather than the species because I know that "Verde", for example, is a tomatillo and not a tomato or pepper. However, if you're not familiar with the varieties or if you have a tomato and a tomatillo both called "Verde" you might want to make a notation on your stick. Of course their seedlings look different, but you may not know that. It never hurts to have an excess of information about the plants close to hand.

It's also nice to keep a garden journal. Right now I'm using a notebook and jotting down an entry whenever I do something in the garden or with the seeds. These were seeded on January 1 (two weeks later than intended). I know from the journal that first germination happened on the 6th and by the 7th I had 4 of one variety and 1 of another germinating. As of today it looks like this: 

So, that's 11 of the 12 cells seeded with Goldman's Italian American have germinated, 4 of the 12 cells seeded with Illini Star (slowpoke!), etc. No peppers yet but they like warmer germination temperatures and in my experience they're just a little slow when they have cooler temps.

Later on, particularly when I harvest, I'll use some special charts to keep track of all the data but I still keep a general record of what I do when in the garden. More on that later.

A few other things... 

I know phrases like "not too soggy but wet enough" are vague. Unfortunately I grow things the way I cook. I've learned over the many years I've been doing this how things are supposed to look, feel, and smell (not normally taste, but sometimes). So, I do it by intuition. I know when the soil is perfectly wet and I know how much bone meal to add to my bucket of seed starting mix. I don't measure things anymore. However, if you squeeze your soil and water runs out, it is way too wet. If the soil doesn't clump together then it's too dry. You can find some specific seed starting mix formulas here.

When watering the flats (from bottom or top) in the winter I use warm water. To inflate peat pellets I use hot or boiling water (don't pour boiling water on your 1020 flats because they'll probably melt). Hot water inflates them fast, cold water takes an age.

This is just my first round of seeds for this season. I used what I had left over from last year. I'm about to order this year's seeds and I'll be starting another round of Solanaceae in a few weeks as well as herbs, flowers, and more cool weather crops.

In case you're wondering what I seeded (some of the germination log is abbreviated, some misspelled!): Tomatoes - Goldman's Italian American, Illini Star, Tess's Land Race Currant, San Marzano. Tomatillo - Verde. Hot Peppers - Fish, Early Jalapeno, Thai Red, Serrano Tampequeno.

Coming soon... Making the yearly plan: How to select varieties, how to time your seed starting and transplanting, how to keep track of the data and use it to make improvements, etc.

So... how do you start seeds?

1 comment:

  1. Even if you are late - you are on top of things. I am just going to plant some eggplant seeds to get a head start. I think our frost-free date is in April (I should know that I guess). I know last year we had a pretty late frost in mid -late April and that was bad!