Day 12: Life Is Hard

It's Day 12 now, and things are happening.

Last night, I stepped all the seedlings up from their 2" Jiffy pots into 4" Jiffy pots and further thinned them out. There's now only one or two seedlings per pot. I used my favorite bagged potting soil (Fafard Professional Mix), but you can use any potting mix. I like Fafard because it has no added fertilizer, so I can control the nutrient environment better. I sweetened the mix with a sprinkle of hydrated lime to raise the pH and started feeding the seedlings with a weak organic liquid fertilizer (I use Fox Farm Grow Big). If you use a potting soil that has fertilizer included—like the ubiquitous Miracle-Gro—skip the feeding.

The seedlings are now back to 2" tall. Here's why they shrunk ... tomatoes that grow from vines and need to be staked up or supported are called indeterminate tomatoes, whereas tomatoes that grow from a bush and ripen all at once are known as determinate tomatoes. The most popular variety by far (and the only kind I'm growing) are indeterminate. Whenever you transplant an indeterminate tomato, bury a portion of the existing stem under the new soil. New roots will spring from the buried stem, making the plant stronger. I buried my seedlings an inch or so, so they're stubbier and stronger than before.

With the transplant finished, it's time to start hardening off the seedlings. This process will slowly acclimate the young tomato plants to the harsher conditions outside. Until now, they've been ridiculously pampered inside ... their own little grow light, no wind, no direct sunlight. If I moved them outside now, they'd never survive. So to harden them off, I'm moving them outside in the morning and leaving them in a sunny, protected part of my yard. For the next two weeks or so, I'll keep them outside for a longer period every day, until they're finally ready to move outside for good.

This means I'm finally ready to start preparing for their lives outside. Here's the deal with tomatoes in South Florida: we have a lot of advantages, but our native soil is not one of them. I'll leave the more detailed explanation for tomorrow, but here's the basic issue: you either grow in large containers, or you have to amend and improve the soil. Either way, plan on lugging around bags of soil amendments or potting mix.

One final thought about growing straight in the ground ... our native soil is also teeming with parasitic bugs called nematodes, which live in the ground and attack plant roots. These things love tomatoes, and infection is almost guaranteed. Infected plants begin to lose leaves from the bottom up.

Fortunately, growers have developed varieties that are at least partly resistant to nematodes. When you're shopping for tomato plants, you might see the letters "VFN" after the varietal name. These letters mean the plants have been bred for resistance to three common problems: verticillium wilt, fusarium wilt, and nematodes. Most experts recommend using VFN-resistant plants in the ground in South Florida. Fortunately, some of the most popular homegrown tomato varieties—Celebrity VFN and Better Boy VFN—have both been bred for their resistance. Cherry tomatoes, too, don't seem especially bothered by nematodes.

Sadly, many of the beefsteak and heirloom tomatoes that people love are not resistant. So if you're really attached to growing these more exotic varieties, I'd recommend setting up a large container instead of growing in the ground. But don't worry—it's the same amount of work, and you'll still get plenty of fruit.

Up tomorrow: Tomatoes Three Ways.