Blueberry Tree

mossyminds

Anyone tried keeping a “blueberry tree” indoors long-term? I know they’re shrubs, but I’m hoping to train a dwarf variety into a little single-stem standard in a bright room with a grow light and a self-watering pot. Before I jump in, I’d love advice on a few things that are tripping me up:

Cultivar picks: Are there truly low-chill, compact blueberries that do well in containers indoors? I’m seeing names like ‘Sunshine Blue’, ‘Top Hat’, ‘Jelly Bean’, ‘Peach Sorbet’. Any standouts for indoor fruiting and manageable size?
Dormancy hack: How do you give them enough chill hours inside? Unheated garage, near a drafty window, or is “fridge vacation” actually a thing people do without hurting the plant? How many weeks works, and what temps are safe?
Training to a “tree”: If I choose one leader and prune into a mini standard, will that tank fruiting or just reduce the total yield a bit? Any pruning pattern that keeps it tidy but still productive?
Self-watering pots: Blueberries hate soggy roots, but I love SIPs. Has anyone run a very airy, barky mix in a SIP without root rot? What wicking setup and mix ratio worked for you?
Acid and water: My tap is alkaline. Best practical way to keep pH in the 4.5-5.5 range indoors: rain/RO water plus acid (citric? vinegar?) or ammonium sulfate fertilizer? Any dosing tips that are safe for edible plants, and target EC you aim for?
Soil mix: Is a peat/pine bark/perlite blend still the go-to? Any success (or disasters) with coco for blueberries?
Nutrition: Do you avoid nitrate-heavy fertilizers and stick to ammonium forms? How often do you feed in an indoor setup?
Pollination indoors: If it’s “self-fertile,” do you still see better set with hand pollination? Toothbrush trick vs tapping-what actually works?
Light and seasons: If I simulate seasons, what photoperiod/temperature shifts help signal bloom and then fruiting? Any PPFD targets that kept plants compact but productive?
Pests/disease: What tends to show up on indoor blueberries (mites, thrips, gnats?), and any food-safe prevention routines that actually work?
Mycorrhiza: Worth adding ericoid mycorrhiza in containers, or does regular fertilizing negate the benefit? How do you keep them alive if you’re also acidifying water?

If you’ve grown a blueberry indoors for more than a year-especially in a SIP or as a mini “tree”-I’d love to hear what you’d repeat or avoid.

PlantPeace

A few specifics that have actually worked for indoor/container blueberries:

Cultivars: Go with low‑chill southern highbush or true low‑chill dwarfs. Standouts: Sunshine Blue (₁₅₀-200 chill hrs, compact, self-fertile, reliable indoors), Biloxi (₁₅₀), Misty (₃₀₀), Sharpblue (₁₅₀-200). Peach Sorbet (₃₀₀) is compact and workable. Skip Top Hat for indoor fruiting; it’s very high chill and underwhelming indoors. Even with “self-fertile,” pairing two low‑chill cultivars helps set.
Dormancy: Aim 200-300 hours at 1-7°C (34-45°F). An unheated garage works if roots don’t freeze. “Fridge vacation” is viable for small containers: 2-4°C (36-39°F) for 6-8 weeks, plant bagged to limit desiccation, watered lightly every 3-4 weeks, kept away from produce (ethylene). Reduce daylength/feeding ahead of chill to harden.
“Mini‑standard” training: Select one strong cane, stake, and clear laterals up the first 20-25 cm to form the trunk. Keep 3-5 short fruiting laterals in the top “head.” Renewal prune 1-2 of the oldest laterals each year after harvest. Expect some yield loss the first 1-2 years but good production once the head is built; replace the trunk every ₄ years if vigor wanes.
SIP/media: Works if you limit saturation. Use a small wicking area (a pair of 6-8 mm polyester wicks) and a 2-3 cm air gap above the reservoir. Media: 60% aged pine bark fines : 30% peat : 10% perlite, plus 2 g/L gypsum and ₁ g/L elemental S. Top‑water to full runoff monthly to flush salts; keep reservoir EC <1.2 mS/cm. Fabric grow bag set into a sleeve improves aeration.
Water/acid: RO or rain is best. Acidify to pH 4.8-5.2; citric acid is food‑safe and stable enough for small setups (vinegar is weak/variable). Feed 60-120 ppm N as ammonium sulfate in active growth (≈1.1-2.2 g per US gallon), target solution EC 0.8-1.2 mS/cm. Pause feeding during chill.
Nutrition: Favor ammonium over nitrate; keep P low; add chelated Fe periodically (Fe‑EDTA is fine at low pH). Avoid calcium nitrate; supply a little Ca with gypsum in the mix rather than in solution.
Light/temps: 350-500 µmol·m⁻²·s⁻¹ at the canopy for 12-14 h (DLI ₁₅-25) keeps plants compact and fruits well. After chill, run ₁₈-22°C days and 10-15°C nights to bloom; avoid >27°C during bloom/set.
Pollination: Vibrate flower clusters with an electric toothbrush or tap/stem‑flick daily over the bloom window; even “self‑fertile” plants set better indoors with vibration.
Pests/disease: Expect thrips, mites, aphids, fungus gnats, occasional Botrytis on blooms. Use sticky cards, quarantine, gentle airflow. Bti in the SIP for gnats; 1% horticultural oil or insecticidal soap rotations pre‑bloom for mites/aphids; avoid spraying open flowers.
Mycorrhiza: Ericoid inoculum is beneficial in bark/peat. Mix into the root zone at planting; keep P modest and avoid broad‑spectrum fungicides. Acidified irrigation doesn’t harm it.
Container size: 5-7 gal minimum for dwarfs if you want meaningful fruit; 7-10 gal is easier to keep stable.

Coco can work only if very thoroughly washed/buffered and acidified; it tends to drift alkaline and push K, so peat/bark is simpler and more reliable for blueberries.

chlorophyllchic

Tried this twice (SIP + “mini-standard”). It’s doable, but manage expectations: fruit set is fine, flavor lags outdoor unless you nail chill, light, and root temps.

The real killer isn’t pH, it’s alkalinity. Even if you acidify to 5.0, high KH creeps media up. Keep irrigation alkalinity <30 ppm CaCO3 (RO + a measured citric dose). I aim solution EC 0.8-1.0 and flush hard monthly; SIPs salt up fast on ammonium sulfate.
Chill is root-temp sensitive. A garage at 35-45°F works, but if the root ball warms over 50°F regularly you’ll get messy, staggered bloom. A cheap datalogger in the pot is worth more than arguing hour totals.
“Tree” form: single trunk looks cute but blueberries are crown-renewal shrubs. Mine lost vigor by year 3. Better: 3 strong canes, clean to 8-10″ for a faux standard, then yearly cane renewal. More stable yield.
Bloom indoors needs VPD control more than gadgets. Keep RH ₄₅-60% with gentle airflow; a fan does more for set than an electric toothbrush. I tap stems daily; the toothbrush only on peak bloom, quick buzz per cluster.
Light/temps: cooler nights matter. 65-72°F day, 50-60°F night through bloom kept plants compact and flowers open longer. If you push >75°F days, set tanks. DLI ₁₈-22 mol is a good balance.
SIP tweaks: limit wick area and give a real air gap; fabric pot in a sleeve helps. If you see marginal chlorosis + burnt tips, it’s usually salts, not iron-flush first, then chelate if needed.
Coco: I’d skip. If you insist, cap at 30% of the mix, rinse to death, and expect higher K. Bark/peat just behaves.
Avoid peroxide/bleach anywhere near the root zone if you’re trying ericoid mycorrhiza; they never rebounded for me after a single “clean the reservoir” spree.

Biggest taste upgrade I got was stricter chill followed by a cool bloom phase and disciplined flushing. Everything else was marginal gains.