https://urbanharvestlab.com/ Science-based guides for urban gardening, hydroponics, grow lights, and small-space food growing. en-us Mon, 02 Nov 2026 00:00:00 GMT https://urbanharvestlab.com/blog/containers-planters/repotting-fruit-trees-containers/ https://urbanharvestlab.com/blog/containers-planters/repotting-fruit-trees-containers/ How to repot a fruit tree in a pot: move up a size until the pot gets too heavy, then root-prune and refresh the mix. Sizes and timing from the RHS and UGA Extension. Mon, 02 Nov 2026 00:00:00 GMT containers-planters https://urbanharvestlab.com/blog/hydroponics/aeroponics-home-systems/ https://urbanharvestlab.com/blog/hydroponics/aeroponics-home-systems/ Aeroponics mists bare roots instead of soaking them. Compare low and high pressure, nozzle upkeep and pump dependency to decide if it suits a home grower. Mon, 02 Nov 2026 00:00:00 GMT hydroponics https://urbanharvestlab.com/blog/hydroponics/silica-supplement-hydroponics/ https://urbanharvestlab.com/blog/hydroponics/silica-supplement-hydroponics/ Silicon helps hydroponic cucumbers and strawberries most, tomatoes barely take it up, and potassium silicate raises pH. What the trials show. Mon, 02 Nov 2026 00:00:00 GMT hydroponics https://urbanharvestlab.com/blog/plant-problems/bay-leaves-curling/ https://urbanharvestlab.com/blog/plant-problems/bay-leaves-curling/ Curled, thickened, yellow bay leaf edges are usually bay sucker, which the RHS says rarely harms the plant. Unroll one leaf to check, and rule out scale and cold. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/broccoli-small-heads/ https://urbanharvestlab.com/blog/plant-problems/broccoli-small-heads/ Tiny broccoli heads on a young plant are called buttons. Check transplant age, cold snaps, water and heat, then cut the button and wait for side shoots. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/cucumbers-turning-yellow-falling-off/ https://urbanharvestlab.com/blog/plant-problems/cucumbers-turning-yellow-falling-off/ Tiny cucumbers that yellow, shrivel and drop are usually unpollinated or overloaded. Here is how to tell which, and what to do for standard and seedless types. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/leafhoppers/ https://urbanharvestlab.com/blog/plant-problems/leafhoppers/ Scorched, curling leaf edges on beans or potatoes plus small green insects that scuttle sideways mean leafhoppers. Confirm them and decide what to do. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/millipedes-in-pots/ https://urbanharvestlab.com/blog/plant-problems/millipedes-in-pots/ Millipedes in pots mostly eat rotting matter. When they chew seedlings or strawberries, how to tell them from centipedes, and how to dry out their habitat. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/pepper-plant-wilting/ https://urbanharvestlab.com/blog/plant-problems/pepper-plant-wilting/ A wilting pepper in a pot is usually dry or waterlogged, sometimes diseased. How to tell by the soil, the stem base and whether it perks up after water. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/root-knot-nematodes-pots/ https://urbanharvestlab.com/blog/plant-problems/root-knot-nematodes-pots/ Swollen lumps on roots are either root-knot nematode galls or legume nodules. How to tell them apart, what to do about a pot of infested mix, and what resists them. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/spotted-wing-drosophila/ https://urbanharvestlab.com/blog/plant-problems/spotted-wing-drosophila/ Tiny white maggots in ripe raspberries or blueberries are usually spotted wing drosophila. Confirm with a salt test, then pick often, chill and net. Mon, 02 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/soil-fertilizers/pine-bark-potting-mix/ https://urbanharvestlab.com/blog/soil-fertilizers/pine-bark-potting-mix/ Composted pine bark adds air and lasts longer than peat, but only aged, screened bark belongs in a pot. What extension sources say about size, age and nitrogen. Mon, 02 Nov 2026 00:00:00 GMT soil-fertilizers https://urbanharvestlab.com/blog/soil-fertilizers/when-to-fertilize-seedlings/ https://urbanharvestlab.com/blog/soil-fertilizers/when-to-fertilize-seedlings/ Wait for the first true leaves, check whether your mix already carries fertilizer, then feed at a fraction of label strength. What extension services say, and where they differ. Mon, 02 Nov 2026 00:00:00 GMT soil-fertilizers https://urbanharvestlab.com/blog/urban-gardening/drying-chili-peppers/ https://urbanharvestlab.com/blog/urban-gardening/drying-chili-peppers/ Dry homegrown chili peppers on a ristra, in a dehydrator or in the oven, with the extension temperatures, drying times and dryness checks that keep mold out. Mon, 02 Nov 2026 00:00:00 GMT urban-gardening https://urbanharvestlab.com/blog/urban-gardening/dwarf-pomegranate-in-pot/ https://urbanharvestlab.com/blog/urban-gardening/dwarf-pomegranate-in-pot/ A potted pomegranate needs a large pot, six or more hours of sun, light pruning and a cold, dormant winter. What extension sources say about fruit and timing. Mon, 02 Nov 2026 00:00:00 GMT urban-gardening https://urbanharvestlab.com/blog/urban-gardening/mache-in-containers/ https://urbanharvestlab.com/blog/urban-gardening/mache-in-containers/ Sow mache in pots as summer heat fades, keep it cool and evenly moist, and cut it as rosettes through the cold months. Timing, spacing and frost cover. Mon, 02 Nov 2026 00:00:00 GMT urban-gardening https://urbanharvestlab.com/blog/urban-gardening/propagate-tomatoes-from-suckers/ https://urbanharvestlab.com/blog/urban-gardening/propagate-tomatoes-from-suckers/ Root pruned tomato suckers in water or potting mix: cutting length, how many days, and the latest date to plant for a fall crop, per extension sources. Mon, 02 Nov 2026 00:00:00 GMT urban-gardening https://urbanharvestlab.com/blog/urban-gardening/saffron-crocus-in-pots/ https://urbanharvestlab.com/blog/urban-gardening/saffron-crocus-in-pots/ Plant Crocus sativus corms in a deep pot in late summer, pick the stigmas in autumn, and expect a small harvest. Depths, timing and yield from University of Vermont. Mon, 02 Nov 2026 00:00:00 GMT urban-gardening https://urbanharvestlab.com/blog/urban-gardening/turnips-in-containers/ https://urbanharvestlab.com/blog/urban-gardening/turnips-in-containers/ How to grow turnips in pots: 2-gallon pot for two plants, thin to 3-6 inches, sow in spring or late summer, and pull roots at 2-3 inches across. Mon, 02 Nov 2026 00:00:00 GMT urban-gardening https://urbanharvestlab.com/blog/urban-gardening/winter-sowing/ https://urbanharvestlab.com/blog/urban-gardening/winter-sowing/ How to winter sow in milk jugs on a balcony: which hardy seeds to choose, when to start, drainage, venting in spring and which crops must wait. Mon, 02 Nov 2026 00:00:00 GMT urban-gardening https://urbanharvestlab.com/blog/containers-planters/container-root-hardiness/ https://urbanharvestlab.com/blog/containers-planters/container-root-hardiness/ A plant tag's hardiness zone describes the shoots, not the roots. Extension tables show roots in pots are injured at far warmer temperatures than stems. Sun, 01 Nov 2026 00:00:00 GMT containers-planters https://urbanharvestlab.com/blog/containers-planters/fillers-bottom-large-planters/ https://urbanharvestlab.com/blog/containers-planters/fillers-bottom-large-planters/ Extension guidance on filling the bottom of a deep planter: inert fillers, the quarter-to-third rule, a fabric barrier, and how much soil crops need above it. Sun, 01 Nov 2026 00:00:00 GMT containers-planters https://urbanharvestlab.com/blog/containers-planters/pallet-planters-safety/ https://urbanharvestlab.com/blog/containers-planters/pallet-planters-safety/ Pallets for edible planters: what the HT and MB stamps mean under ISPM 15, why unmarked, stained or coloured pallets stay out, and what a stamp cannot tell you. Sun, 01 Nov 2026 00:00:00 GMT containers-planters https://urbanharvestlab.com/blog/containers-planters/treated-wood-planters/ https://urbanharvestlab.com/blog/containers-planters/treated-wood-planters/ Current residential treated lumber and older CCA, creosote or penta wood are very different things. What EPA and extension tests say, and when to switch to cedar. Sun, 01 Nov 2026 00:00:00 GMT containers-planters https://urbanharvestlab.com/blog/grow-lights/uv-grow-lights/ https://urbanharvestlab.com/blog/grow-lights/uv-grow-lights/ Plants do not need UV for photosynthesis. Trials show it can deepen leaf color and raise phenolics, but it can cost yield and is a hazard to eyes and skin. Sun, 01 Nov 2026 00:00:00 GMT grow-lights https://urbanharvestlab.com/blog/hydroponics/dutch-bucket-system/ https://urbanharvestlab.com/blog/hydroponics/dutch-bucket-system/ How Dutch (Bato) buckets work for tomatoes and cucumbers: perlite, the drain reservoir, recirculate or run to waste, and what extension sources say. Sun, 01 Nov 2026 00:00:00 GMT hydroponics https://urbanharvestlab.com/blog/hydroponics/hoagland-solution-diy-nutrients/ https://urbanharvestlab.com/blog/hydroponics/hoagland-solution-diy-nutrients/ What Hoagland and Arnon's 1950 solution contains, why the stocks stay separate, what the scale demands, and when mixing from salts beats a bottled two-part. Sun, 01 Nov 2026 00:00:00 GMT hydroponics https://urbanharvestlab.com/blog/hydroponics/mixed-crops-one-reservoir/ https://urbanharvestlab.com/blog/hydroponics/mixed-crops-one-reservoir/ Which crops can share one hydroponic reservoir? Compare published EC and pH ranges, see which pairs overlap, and learn when tomatoes and mint need their own tank. Sun, 01 Nov 2026 00:00:00 GMT hydroponics https://urbanharvestlab.com/blog/hydroponics/organic-hydroponic-nutrients/ https://urbanharvestlab.com/blog/hydroponics/organic-hydroponic-nutrients/ Organic fertilizer in a hydroponic reservoir needs microbes to turn it into nitrate first. What the research shows on mineralization, EC and pH swings, and biofilm. Sun, 01 Nov 2026 00:00:00 GMT hydroponics https://urbanharvestlab.com/blog/hydroponics/soil-fertilizer-in-hydroponics/ https://urbanharvestlab.com/blog/hydroponics/soil-fertilizer-in-hydroponics/ Wageningen, Minnesota, Kentucky and Penn State on soil fertilizer in hydroponics: urea and ammonium, missing calcium, precipitates, and when a complete soluble works. Sun, 01 Nov 2026 00:00:00 GMT hydroponics https://urbanharvestlab.com/blog/microgreens/fertilize-microgreens/ https://urbanharvestlab.com/blog/microgreens/fertilize-microgreens/ Microgreens grow on seed reserves, so water is enough for a tray. Trials show a light feed adds yield, and extra nitrogen adds salts and nitrate. Sun, 01 Nov 2026 00:00:00 GMT microgreens https://urbanharvestlab.com/blog/microgreens/microgreens-growing-media/ https://urbanharvestlab.com/blog/microgreens/microgreens-growing-media/ Peat mix, coco coir or a fiber mat for microgreens? What the university trials found on yield, clean harvests and pathogen survival, and how to pick. Sun, 01 Nov 2026 00:00:00 GMT microgreens https://urbanharvestlab.com/blog/microgreens/microgreens-temperature-humidity/ https://urbanharvestlab.com/blog/microgreens/microgreens-temperature-humidity/ Germination wants warmth and a humid cover; growth wants cooler, moving air. The extension figures, what they apply to, and how to avoid a mold-prone tray. Sun, 01 Nov 2026 00:00:00 GMT microgreens https://urbanharvestlab.com/blog/microgreens/microgreens-vs-baby-greens/ https://urbanharvestlab.com/blog/microgreens/microgreens-vs-baby-greens/ Microgreens are cut in 1 to 3 weeks from a shallow tray; baby greens take 3 to 4 weeks and a deeper pot. Extension timing, what the nutrient studies show, and how to choose. Sun, 01 Nov 2026 00:00:00 GMT microgreens https://urbanharvestlab.com/blog/plant-problems/allium-leaf-miner/ https://urbanharvestlab.com/blog/plant-problems/allium-leaf-miner/ Rows of white dots on leek, garlic or onion leaves, then rot at the base: how to confirm allium leaf miner and cover plants for both flight seasons. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/bean-leaves-turning-yellow/ https://urbanharvestlab.com/blog/plant-problems/bean-leaves-turning-yellow/ Yellow bean leaves in a container: read which leaves go first, check the roots and nodules, then rule out wet soil, spider mites, rust and mosaic virus. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/beneficial-insect-larvae/ https://urbanharvestlab.com/blog/plant-problems/beneficial-insect-larvae/ Spiny alligators, flat tapered maggots and puffy tan aphid shells are usually predators at work. How to tell them apart before you spray. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/blueberry-no-berries/ https://urbanharvestlab.com/blog/plant-problems/blueberry-no-berries/ A potted blueberry with no fruit is usually too young, pruned off its flower buds, short of winter chill, or poorly pollinated. How to tell which. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/cabbage-aphids/ https://urbanharvestlab.com/blog/plant-problems/cabbage-aphids/ Waxy gray-green aphid colonies in the heart of kale, broccoli or cabbage are cabbage aphids. How to confirm them, why sprays miss, and what to do. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/carrot-fly/ https://urbanharvestlab.com/blog/plant-problems/carrot-fly/ Rusty tunnels in carrot roots mean carrot fly larvae. RHS, Warwick, Rutgers and UC IPM on netting, sowing dates and why a tall pot is not enough. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/citrus-leafminer/ https://urbanharvestlab.com/blog/plant-problems/citrus-leafminer/ Winding tunnels and rolled new leaves on lemon, lime or orange point to citrus leafminer. UC IPM on how bad it is, why pruning backfires and what actually helps. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/diatomaceous-earth-pests/ https://urbanharvestlab.com/blog/plant-problems/diatomaceous-earth-pests/ Diatomaceous earth kills by contact and only while dry, so watered pots blunt it. What extension says it controls, which type to buy and how to handle the dust. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/fig-tree-dropping-fruit/ https://urbanharvestlab.com/blog/plant-problems/fig-tree-dropping-fruit/ Green figs falling off a potted fig tree usually point to a dry pot, a young or overfed tree, or a late crop that cannot ripen. Here is how to tell which. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/garlic-leaves-turning-yellow/ https://urbanharvestlab.com/blog/plant-problems/garlic-leaves-turning-yellow/ Yellow garlic leaves can be a harvest signal or a problem. Read which leaves yellow, when, and with what spots to tell maturity from hunger, rust or wet roots. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/gooseberry-sawfly/ https://urbanharvestlab.com/blog/plant-problems/gooseberry-sawfly/ Green, black-spotted larvae stripping a gooseberry or currant bush in days are sawflies. How to find them early, pick them off and plan for repeat broods. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/green-potatoes/ https://urbanharvestlab.com/blog/plant-problems/green-potatoes/ Green potatoes have been exposed to light, which also raises solanine. What extension sources say about trimming, binning, and keeping tubers covered. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/mexican-bean-beetle/ https://urbanharvestlab.com/blog/plant-problems/mexican-bean-beetle/ A copper beetle with 16 spots and a spiny yellow grub that lace the underside of bean leaves: how to tell them from ladybugs and what extension says to do. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/onions-bolting/ https://urbanharvestlab.com/blog/plant-problems/onions-bolting/ Onions send up a flower stalk after a cold spell, and big sets bolt most. What extension sources say to do with the bulb and how to avoid a repeat. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/pepper-leaf-spots/ https://urbanharvestlab.com/blog/plant-problems/pepper-leaf-spots/ Spots on pepper leaves usually mean bacterial spot, frogeye, mildew, thrips or sunscald. Size, colour and the leaf underside tell them apart. Sun, 01 Nov 2026 00:00:00 GMT plant-problems https://urbanharvestlab.com/blog/plant-problems/plants-wilting-midday/ https://urbanharvestlab.com/blog/plant-problems/plants-wilting-midday/ Plants that droop in afternoon heat and perk up by evening are usually fine. Check the mix before you water, and know the signs of root trouble. Sun, 01 Nov 2026 00:00:00 GMT plant-problems