Comparing a home-grown or farmer’s market tomato to a vine-ripened grocery store tomato is like comparing fresh squeezed orange juice to water. The flavors aren’t even on the same planet.
Every May, when the first tomatoes lie heavy on the vine, my momma and I start eying the biggest ones and debating when they’ll be ripe. Okay, so we don’t really debate. We lie.
In my family, “it’s not ripe” translates to “get your paws off my BLT”.
Since we can most of our tomatoes, we only grow a few indeterminates. These provide flavorful tacos, bruschetta, and sandwiches throughout most of the summer. Here in the southern reaches of Zone 8, even the most heat resistant tomatoes stop producing when the heat index reaches 100F. All of our tomatoes, including the determinates, generally produce a second crop come fall.
If you require a continuous harvest, focus on indeterminates or succession plant determinates. Determinates work best if you have a short growing season or prefer harvesting the bulk of your crop over 4-6 weeks. This makes determinates more vacation friendly.
The PH Verticillium Wilt Connection
Tomatoes prefer a pH between 5.5 and 7.3 and are most productive when it’s between 6.0 and 6.8. For acidic soils, a heavy application of agricultural limestone both raises the pH and serves as a cheap source of calcium.
Here’s the problem.
Verticillium wilts prefer soil with a pH between 6 and 9. If used alone, liming your tomato beds makes verticillium wilt happy.
If you’ve experienced problems with verticillium wilt in the past, apply elemental sulfur after liming to adjust the pH down to around 5.5. In warmer areas, use soil solarization to help control wilts and other diseases.
Apply 80-90 lbs/acre nitrogen as follows: 1/2 incorporated during pre-planting and 1/4 side-dressed when the fruits reach 1/2″ across with the remainder side-dressed a month after.
Check the oldest leaves on the plant for yellowing or a lighter shade of green—both signs of nitrogen deficiency—before side-dressing your tomatoes. Too much nitrogen creates lush tomato plants with few tomatoes.
Incorporate 100 lbs/acre of phosphorous during pre-planting.
Incorporate 100-200 lbs/acre of potassium during pre-planting.
Despite myths to the contrary, tomatoes absorb calcium through their roots, not their leaves. If you suspect calcium deficiency, add calcium nitrate to your drip irrigation system or incorporate additional calcium during pre-planting.
In general, tomatoes need medium (801 to 1,200 lbs/acre) to high (greater than 1,200 lbs/acre) calcium levels.
Tomatoes grow throughout the continental US. However, growers in zones 8 and higher and in zones 5 and lower should pay close attention to variety.
When daytime temperatures reach 90F, most tomatoes experience some bloom drop. In warmer regions, look for heat set tomatoes or early producers like fourth of July and beefsteak.
In cooler regions, focus on cool set tomatoes. These are more cold tolerant with some claiming to be frost tolerant.
See Tomato Varieties Growth Habit and Disease Resistance and Tomato Disease Resistance Table for more details.
Transplant tomatoes after the daily low reaches 55F.
In warmer zones, transplant fall tomatoes 3-4 months before the first fall frost. For the best fall crop, use determinate varieties that produce a crop less than 75 days after transplanting.
Germination Temperature: 60F-95F; optimum germination at 75F to 90F.
For many years, I started my tomatoes during the first week of January. Damping off struck. Three-quarters of my tomato seedlings died. I restarted multiple times and ended up with transplants that were weeks, sometimes months older than others.
Then I discovered the wonders of the paper towel method. I use unbleached coffee filters, not paper towels, but the principle remains the same.
- Drop tomato seeds on a damp paper towel or coffee filter.
- Fold it.
- Place it in a ziptop bag and leave the top just open enough to stick a pencil in the corner.
- Stick the baggie on top of the refrigerator and check it every few days.
- After the seedlings germinate, gently free the seedling from the paper towel (or tear it) and transplant the seedling to a soil block or soilless plug. Just make sure you have a big enough hole for the root and don’t break the root.
See Seed Germination Theory and Practice, page 9 for further information.
I typically use 2″ soil blocks and then pot them on to larger 4″ and 6″ blocks.
If you’re growing more than 100 tomatoes, you should consider using a float system. See Production of Tomato Transplants in Float System Greenhouse for more information. Note, you can also use these methods to bottom feed and water soil blocks.
Once your tomatoes begin blooming, ensure they receive a steady amount of water. The official recommendation is 20“-25” throughout the growing season. However, there is a balancing act here. The more you irrigate, the less flavorful your fruits will be. However, you’ll have more tomatoes.
Bed width: 5’-6 1/2’
Use double rows for compact plants and single rows for larger plants.
Seedling spacing: 18“-30”
Seed estimate: 1 – 1.5 lbs/acre
Trellised tomatoes are easier to harvest. Trellising also prevents diseases.
For indeterminate tomatoes, prune them to a central leader and wide this around a sturdy piece of polypropylene twine or a hemp rope. Do not use hemp twine. It rots by mid-season.
Place the rope over an A-frame or suspend it from a pulley. As the tomato grows, lower the rope. This keeps the tomatoes within reach for easy harvesting and prevents the fruit from touching the ground.
For determinate tomatoes, use a cage or a Florida Weave, also known as a Basket Weave. Use either wooden stakes or metal t-posts for your Florida Weave. Use polypropylene twine, not hemp twine or any other twine that may stretch.
Do not use PVC pipe stakes. As your tomatoes grow, their weight will make the twine slide down the PVC pipe.
For additional information, see Stake Your Tomatoes.
Although many extension offices recommend using plastic mulch for both weed control and soil warming, there is evidence suggesting black plastic mulch increases disease pressure from verticillium wilts.
Keep your tomatoes weed free.
Harvesting, Storage, and Marketing
For the best flavor, let your tomatoes ripen on the vine. However, mature green tomatoes will ripen off the vine.
If you anticipate a severe storm or merely need to harvest them early, lay your green tomatoes on a tray or place them in a crate. Keep the temperature between 55F and 80F, ideally between 63F and 70F.
Harvest tomatoes in the morning after the dew dries.
To minimize bruising and damage, snip the tomatoes off the plant. Avoid overpacking tomato crates.
At the Market
Display your tomatoes in a shaded area of your market stall. Consider handing out small samples of tomato and basil bruschetta or another uncooked tomato sampler.
If you grew paste tomatoes, hand out a basic marinara sauce recipe.
If permitted by your state’s department of agriculture, add value to harvest by making sundried tomatoes.
Tomatoes may be dehydrated, aka sundried tomatoes, canned, and frozen. Canning tomatoes requires a pressure cooker.
If you prefer tomato sauce to diced or whole tomatoes, a food mill will help you process them quicker.
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