I have been gardening in what I call "glacier slurry" and you call glacier till since '04. The only tool that worked for me was a hand mattack and I dug deep wide holes and perk tested them. My backfill was natural soil and purchased compost because my housepad/gardening area was cut out of a slope. There is probably little plant organic material in the gardening area because of it being cut out of the slope ... except for the decayed mulch material I have applied twice a year over the last several years. The glacier slurry is porous and drains well, which means that anything I use will end up in our water supply, the Trinity River. Until last year, I tried to get by with organics and time-released fertilizers, but the plants just didn't thrive. They did OK, but I knew something was missing. Last spring, after the estimated last frost date in April, I applied 1/4 cup of calcium nitrate to the larger roses and less to the smaller roses. I watered well the day before and then watered again the same day I applied the CN. It was enough to kick start the roses and they did a LOT better last season. Altho' the roses do leaf out earlier than they should, most of that growth is blind growth. I think it's the plant trying to feed itself through photosynthesis. We always get a late frost or snow before the middle of April and that growth generally dies off or gets pruned off. We have temps in the high 90s or low 100s for weeks at a time during the summer and time released foods are just burned up too quickly to be reliable, so last year, I did a combination of organics and synthetics and all of the plants were healthier than in prior years. In my experience, it's hard to find the right balance to feed the plants and not pollute our water source. I think I have planted the last of the roses I am going to plant, except for replacements for roses that don't do well in this climate. I know I don't want to dig any more rose holes in this stuff. Smiles, Lyn

I routinely compost fairly large piles of green grass clippings. I have a pile going now that I am turning daily. It is mixed with some wood ash, kitchen scraps, weeds from the garden, and a gallon bucket of coffee grounds a week. My pile is very hot (I don't have a thermometer, but it is steaming) and shrinks daily, until I add about 3 Honda lawnmower bags full of new green grass clippings every 5 days this time of year. I will carry on like this until the leaves staring falling again in early October, and I have more browns to mix in. I had been mixing in yard bags full of dry leaves I saved from from last fall with my grass clippings up until the end of May, but now they are all gone….Composted and spread as mulch in the garden beds. Ray from his Praxxus55712 channel has several videos of composting nothing but grass piles as well. Spontaneous combustion is the last thing I would worry about in any backyard compost operation. The thought of it happening had never even crossed my mind until I read this thread, and hopefully will not occupy my mind again!

I only mulch with compost. I apply it whenever - spring, fall, midseason (with new plantings). I doubt it makes any difference - the benefits of compost are not directly seasonally-related. It adds to soil fertility and tilth and provides the benefit of an insulating and weed suppressing mulch regardless of the time of year applied so do it whenever most convenient for you. Since I have considerably more personal gardening time in fall than I do in spring, my compost mulch tends to get applied most often after fall division, transplanting and clean-up. btw, rountine mulching with compost will negate any need to apply any supplemental fertilization in almost all gardening situations.

If the choice is between plants getting stunted and pouting in their pots vs. sulking in soil that's a little colder than they like for optimum growth, plant them out, IMO (after hardening off of course). I'm very familiar with weather around Westchester, and if I were you, I'd plant out. The mid-Atlantic/NE coast is not like the PNW. There's no stretch of moderate weather between seasons. One day it's winter, then we have some weeks of wild swings back and forth between unseasonably cold and unseasonably hot with a surprisingly small percentage of days that actually are the average temp for spring, then suddenly it's hot. I wish we had that extended moderate period in spring and fall that you get in some parts of the country, honestly, because even though it can make you impatient to put tomatoes in the ground, it would make it easier to grow crops that like moderate temps. heroes1967: Thanks everyone. Tough for me to harden the plants as I'm away from the house weekdays. I'll get them all outside for a while both days this weekend. Use shade cloth. Several layers. Every couple of days, remove a layer. I have a bunch of old window screens I use. I stack three of them. Then remove them one by one. Plants harden off easily that way without needing a lot of fuss and monitoring. The only thing you really need to worry about is setting up something to act as a wind break if a dry windy day is forecast, especially if temps are cool AND windy. In my experience, cool temps + dry wind will burn plants pretty catastrophically and much worse than sun.