Shop Products
Houzz Logo Print
seedmama

Do you use Tom Clothier's Database?

seedmama
15 years ago

I do, especially this time of year. One of the most common questions in the peak of WS season is whether to plant something "now". The question usually has "too late" or "too early" as part of the subtext. The database lists ideal temperature for germination and how long it should take to germinate at that temp. It also indicates whether a seed needs to be exposed to cold, ie cold stratification and for how long. I use the database as a thumbnail gauge for how early or late something should be planted.

As an example, I was received some hosta seeds in the mail today. I've never sown hosta, so I went to Tom Clothier and looked them up.

It said "Hosta elata, minor, montana, sieboldiana, and ventricosa , Sow at 20ºC (68ºF), if no germination in 3-4 wks, move to -4 to +4ºC (24-39ºF) for 2-4 wks, recycle".

First that tells me they aren't frost tender and don't need to be held until later. Second it tells me that a little cold strat won't hurt, and may help. In other words, it's not too late, but I don't want to wait until the temps here warm up to the mid 80s.

I use the database extensively in the late fall. I take my seeds out of alphbetical order and put them in order by sowing date, with the sowing date corresponding to typical temperatures in my region. I use tabs with ranges of half months (Dec 16-30, January 1-15, etc.) If something needs four months at 24-39 degrees, it would be sown first. Something that needs two weeks at 40 degrees would be sown later in the cold season but not last, and so on. I do this because of the volume of containers I plant. It's not realistic to think I can have everything sown by the end of January. I don't want to come across seeds at the end of the alphabet in mid May only to discover they needed two months of cold to germinate, or would have had peak germination at 50 degrees.

One thing not to do when using the database is to try to mimick the listing exactly. It was designed for greenhouse growers who want to cut to the chase instead of letting mother nature do the work for them. As a winter sower it is best used as a general guideline for determining too early or too late.

Hope this helps someone.

Here is a link that might be useful: Tom Clothier's database

Comments (15)

  • drippy
    15 years ago

    Seedmama, I use it a lot, and pretty much the same way you do. I have found certain personal differences - all my annual poppies & delphs seem to benefit from wintersowing, whereas he says certain varieties of delphs & annual poppies don't necessarily need it. And helianthus may germinate at 70, but wintersowing it doesn't hurt it a bit - in fact, surprisingly, my sunflowers are among my earliest sprouters.

    On the whole, I find that site highly useful, though, I just "tweak" it based on my own experiences.

  • bakemom_gw
    15 years ago

    No. I don't bother.

  • morz8 - Washington Coast
    15 years ago

    I use it often, but it seems to me the suggestions are most often for commercial seed, or seed that has been dried and stored. Seed sown fresh (I normally reference Druse, Making More Plants for fresh seed) may have variations in germination requirements from the Clothiers database as far as temps, sometimes moist chill can be skipped, how quickly they may sprout etc...

  • tiffy_z5_6_can
    15 years ago

    I use it too, mainly as a reference point. Anything that says the seeds would benefit from some -4C to +4C for a few weeks goes out first since I do most of my wsing in late February and especially into March. It is a helpful tool.

  • clumsygrdner
    15 years ago

    I do. It helps me decide what to sow outdoors in the summer instead of spring winter and fall. Very useful stuff!

  • anewgarden
    15 years ago

    I had never seen it before! Very interesting! Thanks

  • dorisl
    15 years ago

    I went there and decided to do my silene tomorrow.

    Thanks for the hint!

    :)
    D

  • duane456
    15 years ago

    I use it when I'm not familiar with a certain plant in question.
    Duane

  • mnwsgal
    15 years ago

    I use several seed germination databases including Tom Clothier. The one I use the most is an old Thompson & Morgan one. I believe that is the same one Donn used to compile a list of plants needing cold stratification. I added the number of weeks of cold strat needed to Donn's list and use it for a quick reference.

    Here is a link that might be useful: T & M Seed Germination Database

  • sheltieche
    15 years ago

    Tom Clothier is one of excellent collection info about so many plants I never heard of. Always look it up and have it bookmarked. What I do with that info is different matter. I also use Dr. Deno book on germination which has some specific info on toughies and then try and see what works best.
    As botany professor explained to me once about lily seed- it has to be kept at exactly 64F degree and then it will germinate under 4 weeks, if not - THEN it goes into second dormancy which must be broken by 4 weeks of cold. That is why Clothier mentions- start at warm, if no luck give 4 weeks of cold...

  • trudi_d
    15 years ago

    I keep it bookmarked as a reference, I think it's valuable for looking up an obscure hardwood to confirm that it needs a minumum x amount of weeks for germination but otherwise, because of experience, I don't need it.

    As botany professor explained to me once about lily seed- it has to be kept at exactly 64F degree and then it will germinate under 4 weeks, if not - THEN it goes into second dormancy which must be broken by 4 weeks of cold. That is why Clothier mentions- start at warm, if no luck give 4 weeks of cold...

    Assanine professor who can't see beyond his own nose to understand that Mother Nature has been doing this far longer than Tom Clothier and doesn't do temps of precisely 64 degrees for four weeks.

    Scientists who forget to think and quote dogma are destructive to the growth of human society.

    Dogma discourages free thought.

  • bibbus 7b
    10 years ago

    I stumbled across it today but I wanted to find the best time to plant arugula, Eruca sativa, and it is not listed. I noticed a number of other vegetables are not listed even with their technical names. Do you know of another online resource for vegetable gardens. Its pretty easy to know what to plant in the spring but in the fall, with weather temperatures staying so hot later in the year, it would be much more helpful.

  • jacqueinthegorge
    10 years ago

    Bibbus, take look at this -

    www.territorialseed.com/product/14053

    Dates should be OK for your zone.

  • bibbus 7b
    10 years ago

    This is very helpful and I just printed it out. I like to put charts like this on the inside of my kitchen cabinets for easy access and to remind me! The reason actual temperatures would be helpful though are for winters like last year, I planted broccoli and Brussels sprouts in late August. They produced into January because the winter was so mild. This chart shows planting broccoli in May or June. The plants would die in the 90 degree temperatures of E TN summers. But if this winter gets cold early, I may not be so fortunate as last year! I like the freeze temperatures on this chart. That is very helpful too. Thanks, jacqueinthegorge.

  • moonphase
    10 years ago

    I've never used this but it is just what I was needing.I don't know which seeds needed warm,cold,warm and this will help me with what to sow now or next month.I am so glad you posted this
    moonphase

Sponsored
MAC Design + Build
Average rating: 4.3 out of 5 stars18 Reviews
Loudon County Full-Service Design/Build Firm & Kitchen Remodeler