Why you (probably) shouldn’t be starting seeds yet

As a beginning gardener I learned that to give plants like tomatoes and peppers more time to grow and produce the largest possible crop, it was best to start the seeds early indoors.

gazaniaseedlingsAs soon as I learned that, I wondered: Well, if starting my tomatoes 6-8 weeks before transplanting them outside is good, surely 10 weeks would be better, right? Or 12? Or 16?

Turns out, earlier isn’t always better, and here are some of the reasons why.

First, you probably don’t have enough light. If, like most home gardeners, you are starting seeds under florescent bulbs, it is difficult to give sun lovers like tomatoes and peppers enough light. Light intensity drops off rapidly as you move away from the bulbs, so you know to keep the bulbs right above your seedlings. This works great when the plants are small, but as they grow it becomes very difficult to give both the tops and the bottoms of the seedlings enough light. The result is dying lower leaves and spindly, unhealthy growth.

rootboundSecondly, you are almost certainly going to get some crappy root systems. If you’ve followed this blog for a while, you’ve no doubt read Bert and Linda talking about all the potential problems with the root systems of container grown trees and shrubs. Well, most of the same problems develop with other plants grown in small containers. The roots start circling and they are slow to grow out of the rich soil of the container and into the native soil around them once transplanted into the garden. The longer your transplants grow indoors, the more likely they are to develop problematic root systems. Keeping transplanting them up to larger and larger containers can help mitigate the problem, but that quickly takes up far more space than most home gardeners have for there seedlings.

How big and impact that circling root system will have on the health of the plant varies by species. My personal experience growing zinnias, for example, is that they handle circling, pot-bound roots so poorly that plants from seeds sown directly in the garden quickly over-take and out-perform plants started weeks earlier indoors.

So follow the recommendations for the timing of seed starting. It really does work better. You should be able to get advice on when to start seeds from the catalogs you are shopping, extension offices, or you can use Margaret Roach’s excellent seed sowing calculator.

If you DO decide that earlier is better, that you can provide the light and generous pot sizes to avoid problems, there’s no harm in giving it a shot. But if you do, try starting a second batch at the later, recommended, time and growing the two side-by-side in the garden so you can really compare and see which perform best in the actual conditions of your garden, and if all that extra time and space under your lights or in your greenhouse was really worth it.

Joseph Tychonievich

Blast from my petunia past

A few days ago I recorded a podcast with Margaret Roach were we talked about all our favorite seed sources. One of the many things we mentioned were the great species petunias available from Select Seeds. Which caused me to flash back to my time in graduate school doing research on petunias, and dig up these old images.

Petunia integrifolia (top left) Petunia axillaris (top right) and their F2 hybrids (everything else)
Petunia integrifolia (top left) Petunia axillaris (top right) and their F2 hybrids (everything else)

At the top are Petunia integrifolia (purple) and Petunia axillaris (white) and below are an assortment of flowers from a population of F2 hybrids between the two. This cross is interesting because it is a recreation of the original hybrid that created modern hybrid petunia.

Petunia exserta (top left) Petunia axillaris (top right) and their F2 hybrids (everything else)
Petunia exserta (top left) Petunia axillaris (top right) and their F2 hybrids (everything else)

But more fun is a similar cross with the one hummingbird pollinated petunia, P. exserta! It is fun to see the ways the colors and flower forms recombine in new ways in the seedlings.
I don’t have anything profound to say about these pictures… just, hey, isn’t genetics cool?
Joseph Tychonievich

2015’s top plants in my garden

For normal people, I gather, New Years is all about making resolutions to loose weight or spend more quality time with family. For me, New Years means reviewing everything I grew in the garden in the past 12 months and deciding what I love and what I’m over. I always try lots of new things, and so I thought I’d share my top new favorites for 2015.

Dianthus chinensis 'Chianti' and 'Victoriana'
Dianthus chinensis ‘Chianti’ and ‘Victoriana’

The only Dianthus chinensis I’d grown before are the modern selections which are about three inches tall with huge flowers and as ugly as can be (in my opinion) but ‘Chianti’ and ‘Victoriana’, two charming old-fashioned seed strains won my heart in a big way this year. Annuals, very easy from seed, and blooming all summer with these wonderfully romantic double blooms that made wonderful, long-lasting cut flowers. I’m hoping they decide to self-sow and return next year.

Populus alba 'Richardii'
Populus alba ‘Richardii’

Poplars are, generally, terrible trees. Weak wooded, short-lived, and weedy with few redeeming characteristics. But I bought this Golden Poplar, Populus alba ‘Richardii’, on a whim, and am absolutely thrilled with it. The foliage stays this bright, beautiful shade of yellow all summer, even in full sun (or at least what passes for full sun in cloudy Michigan) without burning. Great in the garden, and cut branches look amazing in a vase. I suppose it could eventually get large, but I’m planning to keep pruning it back hard to the ground to force it to push out lots of lush, long new stems of bright leaves.

'Little Comet' x h2.3
‘Little Comet’ x h2.3

I love breeding plants, and for the past few years I’ve been deeply obsessed with breeding gladiolus… I had a lot of new seedlings this year, but this one, a cross between the wonderful variety ‘Little Comet’ and one of my unnamed hardy varieties I call h2.3, is my favorite of the year. I just LOVE those colors, and love that the come on a strong stem that doesn’t need staking. If it keeps performing well, I’d love to make it available for sale in a few years.

Finally, I forgot to get a picture of this, but I have a new favorite tomato! For years, my favorites have unequivocally been ‘Black Krim’ for large tomatoes, ‘Matt’s Wild Cherry’ for cherries, and ‘Opalka’ for paste, but ‘Black Krim’ has been replaced! My new favorite: ‘Sweet Scarlet Dwarf’ This plant combines a wonderful compact, tidy, attractive growth habit with big yields and really terrific flavor. It isn’t widely available (the only source I know is Heritage Seed Market) but do track down some seeds. You’ll be happy you did.

Now, please, let me know your favorites in the comments so I can expand my shopping list for 2016!

Joseph Tychonievich

Why some plants are “fooled” by a warm December and some aren’t

Here in Michigan – and, it seems, most of the Eastern US – we’ve been having unseasonably warm weather and there are odd things afoot in the garden. Some plants that would normally be dormant coming back into growth. But perhaps odder is that while some plants have been “fooled” by the unseasonable heat, others are still resolutely dormant and not pushing any growth at all despite the warmth. Why is that?

A wild rose with buds still tightly dormant despite unseasonable warmth
A wild rose with buds still tightly dormant despite unseasonable warmth
A 'Knock Out' rose pushing growth during a warm spell.
A ‘Knock Out’ rose pushing growth during a warm spell.

There are a lot of factors that determine when a plant is dormant and when in active growth, a key one in this context is whether they have a vernalization requirement or not. In simple terms, some plants, once they go dormant for the winter, will refuse to come back into growth until they’ve experienced a period of cold temperatures. Once they’ve been through that cold, the plant is termed to be vernalized and will then burst into vigorous growth as soon as the weather warms up again.

You’ve probably run up against a vernalization requirement in terms of bulbs like tulips. That requirement is why you need to give tulip bulbs a cold treatment in order to force them to bloom indoors, and why southern gardeners without sufficient natural winter cold have to pre-chill their tulips in order for them to bloom. The adaptive advantage of this is obvious in a year like this, as it prevents plants from jumping the gun in a mild December and getting damaged by the real cold when it arrives.

So why do are some plants lack this adaptation and come into growth in a freak warm spell? Some are adapted to life warmer climates and sometimes it is the work of humans. Modern hybrid roses, for example, have had their vernalization requirement bred out of them. The downside is that this makes them more susceptible for winter damage sometimes, but the plus side is that it is part of what causes them to bloom all summer long rather than just once in the spring the way most of their wild ancestors do.

An idea worth stealing: Mesh pots for bulb collections

Last year I was in England, and a snowdrop obsessive there (aka, a Galanthophile) showed me this cool trick, using mesh pots to keep her vast collection of different varieties organized.

meshpot

She puts her bulbs in these pots (designed for use in hydroponic systems, I believe), and then sinks the entire pot down in the ground, so that the pot is invisible. The pot keeps the bulbs contained and easy to find so you can dig them up to divide or share even when dormant, and keeps different varieties growing next to each other from getting mixed up. But unlike a regular solid-sided pot, the open mesh allows roots and water to move freely so the bulbs grow just as easily and with as little care as if they were planted directly in the ground.

Corydalis turtschaninovii
Corydalis turtschaninovii

I’m not a snowdrop lover, they frankly bore me, but I have been getting more and more obsessed with bulbous corydalis, selections of C. solida and the amazing true blue Corydalis turtschaninovii. The tiny bulbs are impossible to find once they get dormant, and my collection is already beginning to get mixed up as the different varieties begin dividing and encroaching on each other… I’m going to start planting new editions in mesh pots to keep everything organized.

Joseph Tychonievich

The “safe seed pledge” is meaningless

The seed catalogs have started showing up in the mail, and a great number of them include something like this on the first few pages:

safeseed

Here’s the thing: NO ONE is selling genetically engineered seeds to home gardeners. There is one company, funded by kickstarter, that is trying to sell genetically engineered seeds of a glow-in-the-dark plant sometime in the future (though, like a lot of kickstarter project, the actual release date keeps getting delayed) but other than that, genetically engineered varieties are only being sold to commercial farmers, and only after the farmer has signed a pretty comprehensive licensing agreement.

You can go to the store and buy food made from genetically engineered varieties — essentially anything that contains corn and isn’t labeled as organic will be — and you can stop by the pet store and pick yourself up a fish with jellyfish genes, but no one is trying to sell you genetically engineered seeds.

So those pledges in seed catalogs promising they contain no GMO seeds are technically true, but also pretty meaningless. So if you are worried about accidentally getting a GMO variety, don’t be. And if you wish you COULD grow one, sorry, you are out of luck, unless that kickstarter project ever actually gets up and running.

— Joseph Tychonievich