Tomatoes: A not-so-scientific growing experiment. Week 5 update

Updated: Sep 14

Oh no! Some of the plants blew over even with their cages; tomato plants 7 and 9 were particularly bad. I think that the cages just didn’t provide enough structural support since they are also in the grow bag instead of being directly in the ground’s soil where they go be pushed deeper down.

Tomato plants in various amounts of compost and topsoil
Week 5 update: compost / soil experiment

All plants continued to grow well; plants 7 and 9 (60% and 80% compost, respectively) unfortunately had about 10 inches of sideway growth. Thus, their measurements are now going to be shorter than the rest, all else equal. I tied the tomato cages to stakes that I put directly in the surrounding clay-based soil (not in the grow bags’ topsoil) to give them a little more support.


As the plants have grown taller, I’ve also noticed that additional space between the plants would have been helpful so that the light would hit the plant leaves lower down (and in the middle of the grouping). Also, the tree that did not grow or produce foliage last year, has started to grow taller and more leaves. This means that plants 5, 7, and 9 are getting just a little bit less light than the rest.


Without further ado, this week’s plant growth information in the compost soil mix experiment:


Plant 1:

0% compost, 10% topsoil

Height start: 14.5”

Height today: 47.5”

Growth: 228%


Plant 2:

10% compost, 90% topsoil

Height start: 16”

Height today: 46”

Growth: 188%


Plant 3:

20% compost, 80% topsoil

Height start: 14”

Height today: 35”

Growth: 150%


Plant 4:

30% compost, 70% topsoil

Height start: 14”

Height today: 41.5”

Growth: 196%


Plant 5:

40% compost, 60% topsoil

Height start: 16.5”

Height today: 47.5”

Growth: 188%


Plant 6:

50% compost, 50% topsoil

Height start: 16.5”

Height today: 45”

Growth: 173%


Plant 7:

60% compost, 40% topsoil

Height start: 14.5”

Height today: 46.5”*

Growth: 221%*

The plant fell over and had about 10 inches of sideways growth that is not well reflected in the numbers.


Plant 8:

70% compost, 30% topsoil

Height start: 13.5”

Height today: 45”

Growth: 233%


Plant 9:

80% compost, 20% topsoil

Height start: 13”

Height today: 42”*

Growth: 223%*

The plant fell over and had about 10 inches of sideways growth that is not well reflected in the numbers.


Plant 10:

50% compost, 50% topsoil

Height start: 15”

Height today: 40.5”

Growth: 170%


Plant 11:

40% compost, 60% topsoil

Height start: 10”

Height today: 40.5”

Growth: 305%


Plant 12:

30% compost, 70% topsoil

Height start: 10”

Height today: 39.5”

Growth: 295%



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