Well, the countdown is officially on. We’re nearing our final 30 days of expected frost free growing days. So, it’s time to talk about how we “force mature” some of our plants.
When it comes to indeterminate tomatoes, these guys have no idea what’s coming for them. 40 below just ain’t their thing. Given their ideal current greenhouse climate, they’d happily keep growing larger and larger. But, we can expect those freezing temperatures to start rolling in in about 30 to 45 days from now. And we want their fruit!
So, one of the northern practices we use is to “top” those tomatoes. Literally, just cut the growing tip off. We’ve been maintaining suckers, vigilantly, as well. This effort helps in two ways. One, it helps the plant focus on fruit maturation as opposed to growing, since we’ve removed all sources of further growth. Secondly, it also sort of “shocks” the plant’s survival instinct and those seeds in the fruit are its primary succession plan.
You’ll notice that when you do this, the indeterminate tomato will make every effort to grow suckers. Sometimes it’ll even start spitting out new stems from the base. All these come off! Again, we want to fully arrest new growth and have the plant focusing entirely on fruit production. As temperatures cool, these efforts should reduce further and further.
In a week or so, we’ll also be removing all unpollinated flowers. The reality is, at this point in the game, any fruit that aren’t yet established have zero chance of getting close to maturity. We’d rather have the plant diverting its resources to the fruit that does have a chance than a bunch of worthless, unusable and immature tomatoes. We hate to be harsh, as hope is strong in gardeners, but facts are facts.
As fruit matures, we try to harvest it as soon as possible. (Being sensible to amounts needed for preservation needs and such.) Every fruit harvested is one less thing the plant has to divert resources to. Almost every late season effort we perform on tomatoes is entirely focused on aiding the plant in completing fruit maturation.
You’ll also notice that we’ve significantly trimmed back the lower leaves on our indeterminate plants. We do this throughout the season, bottom to top, leaving about 1/2 to 1/3 of the plant’s top branches in tact. It’s primarily for good airflow and making space to walk by the plants. But, it also maximizes sunshine on the fruit, which also aids maturity.
Once we started using this practice, our ripe tomato harvests increased quite significantly, probably better than 50%. In most seasons, we’re usually left with very little immature fruit that we have to force-ripen off the vine. We do struggle in particular cool late seasons, but so does everybody.
Like everyone else, we’re hoping for an extended season and a nice fall “few weeks.” But, in the subarctic, winter comes on like a freight train. We find it best to be incrementally prepared for this as once it kicks, there’s literally no stopping it.
