Fertilizer recommendations

Hi, in the middle of sprucing up the front yard and I've planted a 20 ft. Queen and a couple of P. roebellini. The soil around here is nasty clay, so I ammended heavily with about a 50/50 fir bark based compost and a sandy topsoil mix. Also added some EB Stone starter fertilizer to the planting holes. My first time with these types of palms outside and I want to give them the best possible conditions.

Looking for recommendations on fertlizers. The nursery I bought from recommends ironite, but I'm not clear if I should wait for another 4 weeks or so before adding anything. We're getting some light frosty nights and I'm hoping they won't suffer too much shock between the planting and the cold temps.

Just for future referrence, recent studies have shown ammending the soil, particularly to 'nasty' clay, does NOT help palms grow any better, and in fact will often send them into a sulk... 'nasty' clay as you call it here in California is the BEST soil for Queen palms and most Phoenix species and is often nutrient rich, has a nice medium pH and retains moisture. The last study done by Dr. Hodel showed that just digging a hole large enough to fit the root ball into worked best, and back fill with the same dirt you dug out of the hole, NOT ammended soil. This may seem counterintuitive, but experience has shown many growers for this to be the case, and this recent study confirmed it. The study was only done on common species (Phoenix, Syagrus, Butias and Washingtonias.. nothing delicate or costly). Additional fertilizers are also nice, but usually unnecessary, at least for the first year after planting in clay. Watering soon after planting, and often, is the most useful and important step when planting palms here in California. There are a few species of palms that seem to like a different pH, and some slugs and tender palms that appreciate a better draining soil, but most surprising take well to our clay. Heavy mulching the surface with bark or other mulch has been shown to be very helpful in not only making the soil drain better, but also protects the roots a bit. Some mulch up to 1' thick in bark etc. and this has been pretty successful.

Palmbob, thanks for the feedback. I have more to plant and will consider your advice. My primary concern with ammending was for drainage. The end result was probably not the 50/50 I suggested earlier based on how firm the soil is looking today. Certainly not sandy or loose as I expected so the clay content is still pretty high.

Unless you make a good size hill, digging a hole in clay and filling with ammended soil will likely create a bowl (especially if it is a low lying area). I learned that lesson after digging up some dying fruit trees a few years. There was standing water in the hole and they drowned. For standard trees I now have a neighbor with a bobcat and 3' auger drill down 15' or until I hit sand (whichever comes first). I then backfill all but the top 5' with soil from the hole and amend the rest. More than overkill for palms though.

For the backyard (tropical area) we disc-ed in 20 yards each of compost and sand with a tractor and then rototilled. Now have a wonderful 15-18" topsoil layer. All set for the palms and nutrient loving bananas. Overkill, but no more unwanted bogs.

None of these are planted at ground level. So far everything is planted with the rootball 1/2-2/3 above the original grade and ammended soil mounded all around. I do dig deeper than the rootball sits and fill with ammened soil with the intent of creating an area where water can drain away. The process might seem misguided, but I'm trying to do what I can to get these to thrive and not just survive.

Both those species will do fine in poorly draining clay, and the comment about making a bowl of standing water with amended soil is a good one. Recommend next time forget ammending the soil. Add lots of mulch on top and it will promote drainage deep down as it gets worked into the soil. Queens in particular flourish in very poor soils as long as they are wet (never heard of queen rotting from being water logged.. though sitting in a 'bowl' of amended soil would be one way it could happen). Also recommend planting DEEP, not shallow, or roots prone to drying out. Also newly planted palms tend to be sort of shocky for a while and don't send roots down right away, allowing them to be blown over. I understand your reasoning for doing what you did, and I did that back when I first planted stuff... but it's as wrong as you can get. No ammending, and no shallow planting next time. You will see the difference.

Phoenix roebellleni are similarly extremely tolerant of abuse and wide varieties of soils. In their native lands they are almost rheophytes (live in water or water-logged soils). But they do well in sand, clay, low pH, high pH etc... what they don't like is being dried out. Never heard of an unhappy Phoenix roebellenii from being planted in pure clay, as long as it was not let dry out too much.