Asked on Aug 14, 2015

Growing plants in dense clay soil

So I know you need to bust up the clay and throw in a lot of organic materials when replanting. The rule of thumb is that the hole should be 3x the diameter of the root ball.
Geraniums, sage and other plants are now dying one by one. Any clues? I am guessing the water is not draining properly and the roots are rotting away? Any thoughts or solutions???
  8 answers
  • Janet Pizaro Janet Pizaro on Aug 14, 2015
    Try letting the plants dry out between watering. Geraniums do not like to be saturated. Clay soil should always be amended prior to plantinmg.
  • Penny Lindlau Penny Lindlau on Aug 14, 2015
    feel your pain! in NC I leave both these plants in pots, transplanting into larger as they grow. soil is just too dense no matter how much amending. move to protected porch come winter . some come back, some do not depending on how hard a winter.
  • Dee Lowe Dee Lowe on Aug 15, 2015
    Tim I so feel your pain, being born & raised in Ca. I am a love to garden girl. I now live in Las Vegas where its so discouraging to garden. My backyd is open no shade..most of my plants are in pots, doing ok not great. I am having some pretty good luck w/ lantana. I have found the bigger the hole the better & Miracle Grow potting soil mixed w/ some medium mulch helps. I water 3 x's a day careful not to get the foliage wet when the sun is beating on them. Please come back & share any tips you might learn along the way.
  • Virginia Kanzler Virginia Kanzler on Aug 15, 2015
    Gypsum is good to add to clay to break it up. Also, definitely let the roots dry out before watering . . . not to the point of wilt, but if you stick your finger into the soil up to your second knuckle and it still feels moist, don't water.
  • Duv310660 Duv310660 on Aug 15, 2015
    Sharp sand will help your clay drain.
  • Rhonda B Rhonda B on Aug 17, 2015
    Plant above grade or create a raised (or lasagna) bed. This will help keep the roots from sitting in poorly draining soil.
  • I live not too far from you and know what you are dealing with. Rhonda B's suggestion is a good one if you want to go that route or (and I am going against everything that you have read) > stop amending the soil and digging your holes so big! I found out years ago when we bought our current home with compacted, sterile soil that digging bigger holes and amending the soil just caused more problems. The fact is that the clay soil holds water and if you dig a huge hole all you are is making a bigger pit for the water to sit in while the plant drowns and rots. There are certain plants that will not grow in your soil and so you may need to experiment with what will grow (may I suggest natives). I mix natives in with daylilies and hosta and learned that years of mulching has paid off. I also put tons (literally) of composted horse manure down to naturally work its way into the soil. I also learned that in certain areas of my gardens that starting things from seed almost always work out in my favor since seeds grow into the soil. Coneflowers, Salvias, Sages, Black eyed Susans, Gaillardia (blanket flower), and even certain coreopsis will do very well in your soil. Another important tip is to make sure you are breaking up the roots on compacted root balls.I have to be honest but geraniums are off my lift because they do not like my soil. Native wild geraniums may do well too. 4" of mulch is in most of my garden beds too which breaks down and naturally amends the soil. Gardening and getting good soil will take time and I know from experience that it can take at least 3-5 years depending upon what you do. Do not give up you just may need to rethink what you are planting at this stage. See if you can find a source for composted horse manure and spread it on your gardens and work it in the soil. I did this for 2 years to turn an oil covered, sterile piece of yard into a lush shade garden. It takes time. I hope I didn't write too much!