How to transplant tomatoes

If you started your tomato seeds back in January or February, chances are you've got some healthy baby plants ready to go into the ground now.  Scroll down to see how.

If you haven't started your tomato seeds yet, don't fret.  They grow faster this time of year, and can still catch up.  Or for those of you in cold places, it's still too early to transplant your tomatoes outside anyway, and right now is a good time to get those seeds started.

(Fun fact:  Some Bay Area master gardeners did an experiment, transplanting tomatoes at weekly intervals from mid-March through to the end of May.  All the plants started producing fruit at more or less the same time in early July. A couple times, due to moving house or other limitations, I didn't get tomatoes into the ground until July, but I still got a crop starting in late August. You've got perhaps more flexibility than you think as far as timimg.)

Back in February I started experimenting with growing seedlings for transplant in the pots that are the foundation of our microgreen kit, which we're now selling separately as the square seed starting tray because the results were really quite good.

I used the same tomatoes from the picture above in a short YouTube video showing how to separate and transplant them to bigger pots to grow some more before being planted out. (There were about 4 weeks of growth between the photo above and the video below)

Now, another 4 weeks or so later, those same tomato plants are big and strong and ready to go in the ground.

(The two pots on the front of the rows are the same ones from the video.  That's just 4 week's growth!)

Finally our new veggie beds are ready for planting and I got those tomatoes into the ground. I'll have a long post about the build coming soon, for now you can see an abbreviated version on our instagram.

Here's how to plant a tomato seedling to give it the best start.

1. Plant it deep 

Tomatoes can grow new roots out of their stems.  Burying your seedling about halfway up its height causes it to grow tons of new roots, giving the plant a solid foundation for strong growth later.

You can see how tall the plant is before I put it in the hole, above, and after, below.

For a big tomato seedling, you have to dig a pretty big hole!

Fill the soil back in around the plant, burying any leaves whose bases will be below ground.

Space plants about 18" apart in the ground, or in containers with at least 5 gallons of space per plant.  (Some super dwarf varieties can grow in smaller pots.  They'll be marked as such.)

2.  Water Deeply 

After planting, give your tomato plant a good soaking, more water than you think, and then some more.  And then don't water again for a week.  As the water percolates down through the soil, the new roots will follow it, beginning to establish the kind of deep root system that will help your plant find moisture through hot spells in the summer.

Frequent, light watering will encourage shallow roots, which are less resiliant to dry spells and heat.

Keep to a schedule of deep infrequent water through the rest of the summer, adjusting for the weather.

3.  Fertilize

Right at planting time, I like to give seedlings a light feed with dilute liquid seaweed fertilizer to help them through the shock of transplant.  Tomatoes can be hungry plants, and it's a good idea to feed them a few times through the summer with organic tomato fertilizer, or a top dressing of compost, chicken manure, or other amendment.

4.  Provide support

It's a good idea to put in something to support your tomatoes while they're still small enough you can build around them.  I have't done it yet, but I will within the next week or so.  You can buy commercial tomato cages, or build a structure yourself with bamboo canes, rebar, or really whatever you've got.

Fresh tomatoes are still a couple months away, but I'm starting to get excited!  How far along are your tomatoes?