I have a part of the herb garden that has not had a major renovation or anything much in the way of fertilizer since 2008. It is overrun with weeds.
The plan is if it doesn't rain to clear the area of the weeds and salvage the plants there. I want to work in some steer manure and more compost then I am going to replant the herbs mostly plantain and comfrey for now then cover it all in mulch to try to stay ahead of the weeds.
The pH is about 7.8 the phos, calcium and K are all high. It has not been tested recently but it has been tested a couple of times and the results have been pretty much about the same.
I am using the steer manure and I have some vermicast although it probably won't go far. The compost also tests around a pH of 7.8 but it is what I have to work with.
the space is about 5 feet wide and hopefully we will be able to get about 20 ft long. or about 100 sq ft.
How much manure and compost should I add? and how thick can I layer the mulch for weed control? The soil is a mollisol. very sticky and heavy when it is wet.
If this works out, then I'd like to renovate the garden a section at a time and maybe put more medicinal herbs in if I can find something appropriate.
The plants have been shrinking over time so the nitrogen is probably low.
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rainbowgardener
- Super Green Thumb
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- Joined: Sun Feb 15, 2009 6:04 pm
- Location: TN/GA 7b
I wasn't familiar with the term mollisol, so I looked it up. This is from wiki:
Mollisols have deep, high organic matter, nutrient-enriched surface soil (A horizon), typically between 60–80 cm in depth ....As the world's most agriculturally productive soil order, the Mollisols represent one of the more economically important soil orders.
So, if you are blessed with soil like that, I wouldn't think you would have to do much to it, especially for growing herbs, which typically do not require rich fertile soils.
Your issue may be with the alkalinity of your soil. I don't know what all you were growing there, but comfrey prefers a pH of 6 - 7.
You can mulch pretty much as deep as you want. Needs to be at least 3" for weed control, but anywhere on up is fine.
Mollisols have deep, high organic matter, nutrient-enriched surface soil (A horizon), typically between 60–80 cm in depth ....As the world's most agriculturally productive soil order, the Mollisols represent one of the more economically important soil orders.
So, if you are blessed with soil like that, I wouldn't think you would have to do much to it, especially for growing herbs, which typically do not require rich fertile soils.
Your issue may be with the alkalinity of your soil. I don't know what all you were growing there, but comfrey prefers a pH of 6 - 7.
You can mulch pretty much as deep as you want. Needs to be at least 3" for weed control, but anywhere on up is fine.
Thanks rainbow. The soil there is sticky clay. The pH is a problem because it is in a low area with sodden soil. It is 17 ft above sea level. The medicinal garden is not nearly as bad as the culinary garden which will flood and puddle when it rains.
I guess I should no longer classify it as a mollisol because that classification is for undisturbed soil. The garden was last renovated in 2008 when it got its last big dose of compost, chicken and steer manure. The soil test was done after the amendments and chicken manure is now banned because it would just make the pH a lot worse. Very little organic matter (except what falls off the plants or blows in has been added since then and it has had no real fertilizer. Over the years some plants have died and what remains is shrinking in size. The total organic matter has been used up over the years and the dirt now is mostly sticky clay with not a whole lot of organic matter. That is what I will be trying to correct, getting the organic matter back in so the plants can thrive and keep the weeds more manageable.
3 or more inches of mulch for weed control. That's good, I had planned on doing about 4 inches.
Would 2-3 inches of compost and 4-5 bags of manure worked in be enough?
I've done deeper compost in the culinary garden but, It may have been too much. The compost held on to even more water and it was already wet to start with and the plants actually did not like having 6 inches of compost added in. They weren't very happy planted in compost.
I guess I should no longer classify it as a mollisol because that classification is for undisturbed soil. The garden was last renovated in 2008 when it got its last big dose of compost, chicken and steer manure. The soil test was done after the amendments and chicken manure is now banned because it would just make the pH a lot worse. Very little organic matter (except what falls off the plants or blows in has been added since then and it has had no real fertilizer. Over the years some plants have died and what remains is shrinking in size. The total organic matter has been used up over the years and the dirt now is mostly sticky clay with not a whole lot of organic matter. That is what I will be trying to correct, getting the organic matter back in so the plants can thrive and keep the weeds more manageable.
3 or more inches of mulch for weed control. That's good, I had planned on doing about 4 inches.
Would 2-3 inches of compost and 4-5 bags of manure worked in be enough?
I've done deeper compost in the culinary garden but, It may have been too much. The compost held on to even more water and it was already wet to start with and the plants actually did not like having 6 inches of compost added in. They weren't very happy planted in compost.
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rainbowgardener
- Super Green Thumb
- Posts: 25279
- Joined: Sun Feb 15, 2009 6:04 pm
- Location: TN/GA 7b
Yeah, most compost is pretty heavy and dense. Great addition for sandy soils, but adding too much to heavy clay soil might not be the best thing, though some compost is good anywhere. Maybe lighten it up with peat moss or coconut coir (which would bring pH down some too)? The square foot gardeners use Mel's mix, which is 1/3 compost, 1/3 peat, 1/3 perlite (for which rice hulls can be substituted).
You can add as much compost you want. The more the better. Manure should be well broken down,
I have been adding sulpher to my previous house's soil which was of a high PH. You can buy the lower grade, preferably from an agricultural supplier and not a garden centre. Here in SA everything from a garden centre is more expensive.
Acid composts like peat will also help, but it is expensive.
Both must be added every second year or so to maintain as it breaks down. You can search for how to use sulpher to exactly lower the PH to what number you want (only for how deep you cultivate the sulpher in).
I have been adding sulpher to my previous house's soil which was of a high PH. You can buy the lower grade, preferably from an agricultural supplier and not a garden centre. Here in SA everything from a garden centre is more expensive.
Acid composts like peat will also help, but it is expensive.
Both must be added every second year or so to maintain as it breaks down. You can search for how to use sulpher to exactly lower the PH to what number you want (only for how deep you cultivate the sulpher in).
Thanks for the tips guys. I started on a small section. I found out that the sprinkler had been turned off for a while and it was hard to even get the shovel point in the ground so I did not get that far. It was only about 5x10 ft. I did encounter a whole lot of nut sedge and we are digging it out slowly. We found nuts two feet deep. This may take awhile.