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Annuals/flower seeds and soil


QUESTION: Hi, I am starting a business selling cut flowers.  I tested my soil and it has a very high ph so I added sulfur to lower it...I had removed sod in late fall, tested soil added sulfur..Here's my question.  I am going to add 2" good top soil, with the ph being so high should I put cardboard or newspaper down first then add the new good soil over it and plant my seeds.  I am afraid if I don't do something like this that these seeds will do nothing because of the ph and if I'm going to get this business up and running I need to do something asap.  Please give me your advice, any would be greatly appreciated...
Sincerely,  Karen

ANSWER: Karen,
Do you know the exact pH of your soil? I'm assuming you have had it tested, right? Most seeds won't be affected by a pH that's 7.5 or it over 7.5?  

Don't put paper or cardboard down because that will inhibit the roots and make the plants top heavy and prone to drying up quickly. If you're worried about germination you could make a small trench where you're sowing, only an inch or two deep, and fill it with seed-starting mix. But once the plants get growing they will have to deal with the pH in the area. Again, if it's 7.5 or under I wouldn't worry and you can slowly bring the pH down a bit with sulfur.

If you pH is above 7.5 you'll have to address that in order for the plants to do well...and different varieties will respond differently.

You may know this but in order to be complete I'll write it anyway: You'll want to have your soil tested by your local extension service or university soil lab. Home pH tests aren't very reliable so don't make any decisions based on such kits. Your extension or soil lab will explain how to take the sample in that you don't dig from just one small area but combine three or four different samples to get an average for the area where you'll be growing.

Let me know if I can help further,
all the best,
C.L. Fornari

---------- FOLLOW-UP ----------

QUESTION: Hi, yes I tested the soil in 4 different places but I used home testing kit.  It is very high 9 and I know enough about flowers to know that will not work for most flowers.  At least the flowers I'm growing.  Ok I will gather some from different spots and get a hold of a local place.  I wasn't sure about the newspapers so that is good to know..I know it takes time to amend the soil is there anything else I can do besides sulfur maybe compost in the spring before planting the seeds?  I just need to get it ready to go and it's a big part of my business.  I just inherited it and didn't know anything about the soil till I tested it...The grass grows amazing there so I was so surprised by the test results.  Thanks for all the info.  I will call somewhere today to find a place that will read the soil for me..Have a great day!

See if there's a cooperative extension near where you live - they will either be able to test the soil or give you a lead on where to go. After you have the results you might want to use Aluminum sulfate in order to lower the pH more quickly - sulfur is the slowest way. See this good article about lowering pH:

all the best,


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C.L. Fornari


Annuals suggested for specific situations (sun, shade, windowboxes etc) New or unusual annuals are a particular interest of mine, and I grow many of these from seed. I am happy to help problem solve, answer questions about maintenance, and guide you to sources of unusual plants.


I am a garden writer/speaker/consultant and host of a weekly gardening radio program in the Northeast. I have been gardening all my life for my own pleasure, and started as a professional gardener and garden communicator 15 years ago. I work part-time at a garden center, selling and tending shrubs/trees/annuals/perennials...and doing some propagation and design work. I often think that all these professional activities serve to put a somewhat legitimate framework around a serious case of plant-lust.

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