Sunday, November 28, 2010

Dear Brandywine, There's Still Time

Dear Brandywine,

I first heard of you a long time ago, way before I actually started growing tomatoes. I got the idea you were the queen of tomato land—the purest tomato taste, the best-looking fruit, the best pedigree. And it's true, with your deeply burnished shoulders and intoxicating hue, you're the tomato I imagine when I think of the ideal tomato.

This year is the first year I've tried to grow you. We both know how it's going.

I'm not sure if it's you or me. Sometimes I think it's you, to be honest. Sometimes I think you're just temperamental and fussy. Forgive me, but sometimes I think you're high maintenance. And can you blame me? What with your fungal diseases and blossom drop, the caterpillars and the black spot, it's not like you're making this easy on me. I'm working really hard here.

Sometimes I think it's me after all. Maybe I just wasn't meant for a tomato like you. Maybe I live in the wrong zone, or I don't know the secret code, or you're just not that into me.

But here's what I really wanted to say. I'm not giving up on you. Yeah, so this season isn't working out between us. I get it. But I'd like to think I've already learned a few things about you. For example, I think when I grow you again, I'm going to treat for fungal diseases and black spot from the day you go into the ground. I think we need to make some allowances here in Zone 10. That's just for starters.

Anyway, that's just what I wanted to say. You and me? We're not done yet.

Monday, November 22, 2010

Strawberry Power

I'll get to the tomatoes in a second, but this first ...

Behold the Tower of Strawberries. Ha ha. I've been absurdly excited about this method of growing strawberries since I first heard of it a few years ago. For one thing, I'm a strawberry purist—like tomatoes, there's just no competition between grocery store strawberries and fresh strawberries. For another, stackable containers have all the elements I like: it saves space, looks cool, and allows me to control the growing environment.

There are a few kinds of stackable containers out there, but I ultimately went with AgroTower's product. According to the manufacturer, these are designed to work with drip irrigation hoses run up the center column, feeding the individual pots a steady stream of water and fertilizer. I didn't go that far for my first season—I'm hand watering and hand feeding. The pots are designed so water drips down through the column naturally, and although it's a little tricky to water the little pots without washing soil out, it's not that impossible. I know the commercial farms (like this U-pick farm in Delray) all use automatic irrigation, but for one tower, it's no big deal.

Planting was pretty easy. I drove a stake into the ground to give the tower support, then stacked and filled the containers with Fafard 3B potting soil. Overall, I've got 30 strawberry plants, plus six lettuce on the bottom. I rotate the tower every day to make sure all the plants are equally exposed to sunlight. If all goes well, I'm hoping to make jam this year. That's assuming I can keep my five-year-old away from the ripening berries. Last year, I did a few test strawberry plants and I think only one strawberry made it inside. The rest vanished down his gullet as soon as they were even close to ripe. Little monster.

As for the tomatoes, I used Daconil fungicide (chlorothalonil) and the septoria stopped spreading. What can I say, the stuff works. The Cherokee Purple is setting fruit; and the Brandywine is flowering fairly well. I had to get rid of the Heinz because too much damage was done, so I planted a few Big Boys to make up the difference. My schedule looks like mid-season: watering in the mornings; feeding once a week with Espoma Tomato-Tone fertilizer and magnesium; pinching off shoots; and tying up the vines as they grow. These heirlooms aren't as aggressive as some other vines, so they haven't yet hit the top of my cages. When (and if) they do, I'll top the vines to stop the upward growth. In general, heirlooms aren't typically as robust as heavy-producing hybrids, so the plants tend to grow slower, stay smaller and bear less fruit.

Anyway, I'm feeling pretty good—the tomatoes are mostly back in hand. I'm thinking in the future that if I have rapidly spreading septoria like that, I'll spray a lot earlier. Copper fungicide is great stuff for bacterial spot, but it was pretty useless against the septoria fungal spot. I think I could have saved myself a lot of aggravation if I'd treated the vulnerable plants right away. It might even be worth considering treating heirlooms preventively, right after planting. Food for thought ... and another season.

This has also (again) made me appreciate the wonders of modern hybrids. Heirlooms are great tasting, but for sheer production and ease, go with a disease resistant variety.

Monday, November 15, 2010

Happy 'Mater Pictures ...

Things were getting a little grouchy around here, so I thought I'd post some pictures of happy tomatoes.

The top two pictures are Victoria Supreme (an oblong paste tomato), and the bottom picture is yellow pear. How fast a tomato sets fruit depends on the variety—most labels include a "days to harvest" number, which is an approximation of how many days you'll have to wait from planting the tomato until you can start harvesting fruit (if you plant your own seeds, this figure is typically calculated from the day the plant goes into the ground, not the day you plant seeds—add a few weeks for seeds). Most tomatoes range from about 60 days (early harvest) to 80 or 90 days (late harvest). If you want to keep a steady stream of fruit all season long, plant tomatoes with staggered harvest dates ... or just wait another few weeks and do a second planting.

If your tomatoes have been in the ground for a while and aren't setting fruit, there are a few possibilities:

  1. Some blossom drop is pretty common early in the season. As long as it's limited, don't worry.
  2. If you're growing in a very sheltered area, you might want to help them along by hand-polinating your flowers with a Q-tip. Tomatoes are pollinated by the wind, so they need turbulent airflow to spread pollen. People growing in covered patios sometimes have problems with pollination.
  3. The plant could be sick—blossom drop is more common among tomatoes that are suffering from diseases or bug attacks. Check the plant carefully for spotting, discoloration, streaks, and of course, bugs.
  4. Excessive nitrogen in your fertilizer. Using a regular foliage fertilizer can encourage leaf growth at the expense of fruit. Make sure you're using a tomato or vegetable fertilizer (I'll do a post on fertilizer labels soon because this is a pretty big topic).
  5. Excessive heat or humidity. I'm including this for the sake of being complete, but the weather so far this season has really been pretty good. When I walked outside this morning, I thought it was a perfect tomato morning :)
If none of this sounds right, or you want to give you plant a boost, you can buy a tomato set spray. This is basically a hormone that encourages tomato plants to set fruit even in adverse conditions. I've used these before during especially hot years and it works.

Sunday, November 14, 2010

Decision Time

This is not a post I wanted to write.

I've been growing tomatoes for a long time, but this year seems to be the year when Bad Things Will Happen. Despite treating with copper fungicide, the septoria leaf spot I wrote about last week has continued to spread through the tomatoes—even tomatoes that are more than 50 feet apart are all suffering from it.

At first, I couldn't figure out why this year would be so much worse than any other. I've had leaf spot every year and been able to control it with copper fungicide spray (organic), good tomato hygiene and leaf removal. For a while, I thought it might be the mix of heirloom and heritage tomatoes I'm growing, but that argument never really made sense. I've grown heirlooms and heritage tomatoes before with no problem.

The best explanation I can come up with is construction. ("Huh?" you say. "Construction?") Yeah, construction. My neighborhood is the midst of a pretty massive infrastructure project. The roads are all torn up and our cars are continually covered with dust. The pool filter has to be backflushed almost every week. So obviously, there's a lot of particulate matter in the air this year—and fungal diseases live in the ground. My best theory now is that my plants are being coated with airborne fungal spores stirred up from road construction.

Anyway, it doesn't really matter why, because I have to figure out what to do. The copper spray is not working—the disease has continued to spread relentlessly. Here is the breakdown:
  • Brandywine: Lightly affected
  • Victoria Supreme paste tomatoes: Unaffected (this one, btw, is VFFNA)
  • Yellow pear: Severely affected
  • Heinz tomatoes: Severely affected
  • Cherokee Purple: Moderately affected
So ... my decision basically is this: do I switch to a stronger, commercial fungicide? The two best fungicides to control septoria leaf spot are chlorothalonil (sold as Daconil) and mancozeb (sold as Bonide Mancozeb). Of these, Daconil is easier to get—I believe they stock it at most large garden centers. As for efficacy, I looked for studies and didn't really see a consensus. According to North Carolina State University, mancozeb provides superior control for septoria, while some state ag departments I looked at recommended chlorothalonil.

Unfortunately, with the way this is spreading, I think my choice is pretty clear: treat with Daconil (primarily for convenience) or dramatically lower my expectations for this season's crop.


Tuesday, November 9, 2010

Going Ninja

The last few days have been a frenzy of black spots on my young tomato plants. But before I get to methods to control these, it's worth trying to figure out what they are exactly.

There are a number of organisms that can cause black spotting on tomato leaves, especially when the plant first sets fruit. They include Septoria leaf spot (a fungus), bacterial spot (Xanthomonas campestris), bacterial speck, and few others. In general, these are controllable, while some of the more terrifying wilts and blights are killers.

Most of these conditions are caused by the rapid spread of an infectious organism among your tomato plants. Just like in people, these little buggers like warm, wet conditions, so the early part of the season is especially dangerous for us as it's typically still hot and muggy—perfect weather for a bacterial or fungal infection.

In this case, I'm guessing I have Septoria leaf spot, which is characterized by wet lesions on the underside of leaves that develop in black spots with gray centers. Septoria is a fungal infection caused by warm, wet conditions. It is pretty much always present in South Florida, so ... you know, hard to avoid.

I always hate seeing this happen, even though it happens every year.

To control these kinds of diseases, start with prevention. Plant tomatoes in fresh soil, leave them far enough apart that the organism can't easily jump from plant to plant, and never water from overhead.

After you get it, this is what I do: apply a copper fungicide spray according to the label directions (weekly) and religiously remove any affected leaves. Copper fungicide is rated for organic growth, so you can use it on your plants and still have organic tomatoes. So obviously, it's not the strongest fungicide on the market—if you really want to go ninja on fungal diseases, you can switch to a much stronger product such as maneb or mancozeb. These are commercial-strength products.

Personally, I don't use 'em. I cut away leaves, slow it down with the copper spray, and hope the temperatures and humidity break in time for the plant to outgrow the infection. This has worked for me well enough, and I can avoid the stronger fungicides.

As a side note, I'm still really looking forward to the yellow pear tomatoes. EVERYONE loves them. But, man, me and yellow tomatoes have a rocky relationship, and this year is no different. These things are driving me crazy—leaf roll, fungal diseases, and of course, the tomato leaf curl virus. If anyone out there has experience successfully growing yellow tomatoes in South Florida, I'd love to pick your brain ...