Newbie tomato fertilizer question
Hi all -- I started my tomatoes from seed in Feb and they are doing beautifully so far (they've been in the ground and in 20-gallon pots on my deck for over a week now). But I potted them in fertilizer-containing potting mix (e.g. MiracleGro and StaGreen), and one of my raised gardens was filled with garden soil from Lowe's which might have fertilizer in it (I'll have to check the bag). I bought Jobes fertilizer spikes for tomaroes (6-18-6) which say to use two spikes per plant early in the season, but I realize this might be for plants that were put into depleted soil? Will it harm my tomatoes if I use the spikes along with the MiracleGro soil (can one overfertilize?)? I was hoping to boost the phosphorous content for fruit production.