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Belleville MI

I am going to try tomatoes in grow bags. I don't have much space for in ground growing here in suburbia land.

Is there a recommended list of nutrients that help with tomato growing floating around someplace?

Start with 10-10-10?

3/28/2025 10:25:59 AM

Grittyville, WA

Dan says "biology-biology-biology" which is slightly different than 10-10-10 but you can use fertilizer to get biology to decompose brown carbon. There's lots of other goodies you can add. Id check out Dans potting mix recipe/ youtube channel for the most relevant ones.

3/28/2025 11:44:47 AM

Belleville MI

Thanks. I'm growing some of each from Dan's website:

9.44 Domingo x Westerlund
8.44 Big Zac (MacCoy genetics)
5.41 Big Zac (2nd gen MacCoy genetics)

I also have some other Westerlund, Delicious, Big Zac, and Domingo.

I can do up to 7 plants this year.

[Last edit: 03/30/25 10:57:55 AM]

3/28/2025 2:42:44 PM

Belleville MI

I decided to hit up ChatGPT to explore whether it can help me improve upon last years tomato growing efforts. I gave it a list of ingredients and it recommended some suggestions as follows:

To grow giant tomatoes in a 30-gallon grow bag, you need a well-balanced soil mix that provides excellent drainage, aeration, and rich nutrients for sustained growth.

Here’s a recommended ratio for your ingredients:

Base Soil Mix (for structure, aeration, and water retention)

- 40% Organic Coconut Coir (12 gallons) – Retains moisture and improves aeration
- 30% Peat Moss (9 gallons) – Holds water and provides acidity balance
- 20% Perlite (6 gallons) – Enhances drainage and prevents compaction
- 10% Worm Castings (3 gallons) – Provides rich microbial life and slow-release nutrients

Nutrient Amendments (for growth and fruit production) (Mix evenly into the base soil)

- 1 cup Organic Kelp Meal – Provides trace minerals and growth hormones
- 1.5 cups Organic Fish Bone Meal – High in phosphorus for strong roots and fruiting
- 1 cup Organic Blood Meal – Adds nitrogen for vigorous plant growth
- 1/2 cup Mycorrhizae – Enhances root development and nutrient uptake
- 1 cup Gypsum – Supplies calcium and sulfur to prevent blossom-end rot

Additional Notes:

- After mixing, moisten the soil slightly before planting.
- Replenish nutrients every 4–6 weeks with compost tea or organic fertilizer.
- Monitor pH (aim for 6.2–6.8) and adjust with lime if needed.

I have no idea whether this is a good list in the right ratios, or if it will be better than some Miracle Grow above ground bed mix, but it might be fun the do some comparisons.

[Last edit: 04/02/25 12:27:14 PM]

4/1/2025 6:45:10 PM

Belleville MI

I am looking forward to tomato growing season this year. I am going to try some new approaches to see if I can get some better sizes. I'm aiming for 5#'s plus in 2025.

I've been growing in Earthboxes (EB'S) for years, largely because my wife used to work closely with the inventor's son, and partly because I have very limited space here in suburbia land. They work well for casual growing and some farmers in Florida grow in them commercially.

(1) I plan to grow one plant according to the standard EB instructions (basic granular fertilizer like 5-5-5 and garden lime;

(2) one plant in an EB using the same growing medium but with a mix of Kelp Meal, Fish Bone Meal, Blood Meal, Mycorrhizae, and Gypsum;

(3) one plant using a 30 gallon grow bag with the nutrients from (2) and the standard EB growing medium;

(4) one plant using a 30 gallon grow bag with the nutrients from (2) and a growing medium of Coconut Coir (4 parts), Peat Moss (3 parts), Perlite (2 parts), and Worm Castings (1 part), which just-for-fun I got from a ChatGPT query.

I have no idea about the effectiveness of the grow medium recipe in #4, so suggestions are welcomed.

The comparison will only really work by using the same seed in all four, but I'm doing this for fun so I might not actually grow the same seeds in all three.

I've got room to grow 4 more plants in 30 gallon grow bags and/or EB's. Seven plants should increase the odds for a new personal best. I'm pretty sure that a bigger container increases the potential size significantly.

4/3/2025 12:28:06 PM

Belleville MI

I've been doing more reading today. The AI mix has about 75% too much coir. More coir than peat moss would be unconventional.

[Last edit: 04/05/25 8:45:19 AM]

4/4/2025 10:00:42 PM

Colorado

Take AI with a grain of salt. I will literally make stuff up. Its great for telling you a story but its pretty sketch for real actual info.

4/5/2025 12:08:11 AM

Colorado

here is groc's response lol

To grow giant competition tomatoes, you’ll need a soil mix that provides excellent drainage, aeration, and nutrient availability while supporting robust root development. Based on insights from experienced growers and competition-level gardening practices, here’s a breakdown of an optimal soil mix:

A good starting point is a blend of 40% compost, 30% peat moss or coco coir, 20% perlite or vermiculite, and 10% aged manure or worm castings. This mix ensures a balance of moisture retention, aeration, and fertility—crucial for growing massive tomatoes that can weigh 2-10 pounds or more.

Compost: Use well-rotted, high-quality compost (e.g., from leaves, grass clippings, or vegetable scraps) to provide a slow-release source of nutrients. It also improves soil structure.
Peat Moss or Coco Coir: These retain moisture and keep the mix light. Coco coir is a sustainable alternative to peat moss and has a more neutral pH, which tomatoes prefer (target pH 6.0-6.8).
Perlite or Vermiculite: Perlite boosts drainage and aeration, preventing root rot in the dense, water-hungry root systems of giant tomato plants. Vermiculite can work too, but it retains more water, so adjust based on your climate.
Aged Manure or Worm Castings: These add a nutrient punch, particularly nitrogen, phosphorus, and micronutrients. Worm castings are especially prized for their microbial activity, which supports healthy root growth.
For competition-sized tomatoes (think varieties like Big Zac, Mortgage Lifter, or Domingo), you’ll also want to amend the mix with:

4/5/2025 12:12:06 AM

Colorado

Bone meal or rock phosphate (for phosphorus to boost fruit size).
Epsom salt (1-2 tablespoons per plant) or a magnesium sulfate source (for magnesium to enhance photosynthesis).
Crushed eggshells or a calcium supplement (to prevent blossom-end rot, a common issue with giant fruits).
Mix this thoroughly and test the pH—adjust with lime (to raise) or sulfur (to lower) if needed. In practice, many growers prep their soil in raised beds or large containers (20-50 gallons) to control the mix and drainage better than in-ground planting.

Pro tip: Giant tomato plants are heavy feeders, so plan to top-dress with compost or a balanced organic fertilizer (e.g., 5-5-5 or 10-10-10) every 2-3 weeks during the growing season, and water consistently—about 1-2 gallons per plant daily, depending on size and weather.

This mix gives your plants the foundation to chase those jaw-dropping, ribbon-winning fruits. What variety are you planning to grow?

4/5/2025 12:12:24 AM

Belleville MI

Domingo, Big Zac primarily and a Delicious and/or Westerlund

[Last edit: 04/05/25 8:49:25 AM]

4/5/2025 8:49:07 AM