Tomatoes & Sowing Times Before Last Frost


We need to breach the topic of tomatoes! People will soon start talking about sowing them and it’s important to know that your general garden capabilities will have a serious impact on whether that’s a good idea right now, or not.

There’s a lot of flexibility in the sowing time of tomatoes. Generally speaking, you can sow them between 5 and 10 weeks prior to the last frost. That’s a huge range!

We’ve heard of some gardeners that sow their tomatoes 12 weeks to last frost. We think that’s crazy town nutso here! They will be absolutely ginormous by the time we get to sane garden transplanting times! But, in more recent years, we have been sowing our tomatoes about 10 weeks to last frost, or around now. Let’s talk about what that actually takes!

We have access to fully climate controlled greenhouse. That means we can start moving our tomatoes out of our indoor grow rooms, and into this greenhouse, about a month before last frost. (Or, about 6 weeks from now.) If we didn’t have that, there is zero chance we’d be sowing tomatoes this early! Even with this early sowing, our tomatoes will still get a bit unruly to take care of, approaching 3+ foot tall when we get to actual transplanting time! It presents several difficulties, from keeping them hydrated to actually transplanting those monsters! It’s not uncommon for us to have a casualty or two, large vining plants can be a bit risky to transport and move where they are needed.

If you don’t have that greenhouse and are looking for a more sane approach, sowing tomatoes 8 weeks to last frost is the very earliest we’d recommend. You can even get by with 5-6 weeks before last frost and still get a meaningful harvest from them. (Even outdoors!) The later you sow tomatoes, the more manageable your plants will be overall. This can be really important for new gardeners, taking care of “big plants” in a nursery type setting can really throw beginners a curve ball.

There is only a moderate benefit to sowing tomatoes super early, too. Compared to sowing 8 weeks out, we see maybe 10% additional production. Also, only a week earlier maturation. Growing indeterminates here, we see 10 foot tall plants as opposed to 8 to 9 foot tall. You’re not going to “double your harvest” by trying to get ahead, just cause yourself troubles you may (or may not) be prepared for.

That’s All We Wrote!

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