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🌿 Furrow Picks

The garden supplies we actually recommend.

Every fertilizer, seed and tool below is one Furrow recommends inside the app — pulled from the same catalog that powers the Fertilizer Advisor and Seed Finder. Organized by what the plant needs, not by what pays best.

77 products
10 categories
0 paid placements
How this page is funded. Furrow is an independent app with no ads and no subscription. Links on this page are Amazon affiliate links, which means a purchase made through them earns a small commission at no extra cost to you. As an Amazon Associate, I earn from qualifying purchases. Products are chosen on horticultural merit first — several recommendations here point to brands that pay nothing.
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Feeding, amending and testing

Organic Fertilizers

Fertilizer is the single highest-leverage thing most gardeners get wrong. The three numbers on every bag — N-P-K — tell you what the plant gets: nitrogen for leaves and stems, phosphorus for roots and flowers, potassium for fruit quality and disease resistance. Leafy greens want a high first number. Tomatoes and peppers want the first number low once they start flowering, or you get a six-foot plant with no fruit.

Rule of thumb: Match the ratio to the growth stage, not the plant

Soil Amendments & Micronutrients

Amendments fix the soil rather than feed the plant. Reach for these when a soil test comes back short on something specific, when your pH is fighting you, or when yellowing between leaf veins points to an iron or zinc problem that more nitrogen will not solve.

Rule of thumb: Test before you amend — guessing wastes money and can make things worse

Worm Castings

Castings are the gentlest way to add both nutrition and biology at once. The N-P-K looks unimpressive on the bag, which is the point: you cannot burn a seedling with castings, and the microbial load does more for long-term soil structure than the nutrient numbers suggest.

Rule of thumb: Safe on seedlings — mix into the top inch or brew as a tea

Potting & Container Mix

Container plants live in whatever you put in the pot. Garden soil compacts into a brick in a container and drowns roots. A real potting mix stays porous for years and is worth the price difference over generic bagged dirt.

Rule of thumb: Never use garden soil in containers

Not sure what your garden needs?

Furrow's Fertilizer Advisor reads your plant, growth stage and soil pH, then tells you the exact N-P-K ratio to apply and when — so you buy one right bag instead of three wrong ones.

Download Furrow — free

Seeds by crop

Vegetable Seeds

Starting from seed costs a fraction of buying nursery starts and opens up varieties no garden center carries. The catch is timing — sow too early and you get leggy transplants, too late and you miss the window. Furrow calculates the sow date for your zone.

Rule of thumb: Check your frost dates before you sow

Herb Seeds

Herbs are the best return on effort in any garden. Most are fast, forgiving, and productive in a container on a balcony. Basil and cilantro in particular are so much better fresh that growing them changes how you cook.

Rule of thumb: Succession-sow cilantro and dill every 3 weeks — they bolt fast

Flower & Pollinator Seeds

Flowers are not decoration in a vegetable garden — they are infrastructure. Zinnias, cosmos and sunflowers pull in the bees and hoverflies that pollinate your squash and eat your aphids. Coneflower and black-eyed Susan are native across much of the US and support far more wildlife than ornamental imports.

Rule of thumb: Plant flowers near your vegetables, not in a separate bed

Microgreens & Sprouting

Microgreens are the fastest crop in gardening — most are harvestable in 7 to 14 days, indoors, year-round, with no light beyond a sunny window for some varieties. The best entry point for anyone who thinks they cannot grow anything.

Rule of thumb: Harvest at the first true leaf for the best flavor

Starting seeds and measuring soil

Seed Starting & Equipment

Two pieces of gear change seed-starting success more than anything else: bottom heat to get germination going, and real light once they sprout. A sunny windowsill is not enough light — it produces stretched, pale seedlings that never recover. Everything else is convenience.

Rule of thumb: Heat mat for germination, grow light immediately after

Soil Testing & Meters

A soil test is the cheapest gardening purchase you will ever make. Most struggling gardens have a pH problem or one specific deficiency, and both are invisible until you measure. Feeding a garden without testing is guessing with money.

Rule of thumb: Test once a season — pH drifts, especially in containers

Common questions

What do the N-P-K numbers on fertilizer mean?

N-P-K is the percentage by weight of nitrogen, phosphorus and potassium in the bag. A 5-3-3 fertilizer is 5% nitrogen, 3% phosphorus, 3% potassium. Nitrogen drives leafy green growth, phosphorus supports roots and flowering, and potassium improves fruit quality and disease resistance. A high-nitrogen fertilizer on a flowering tomato gives you a huge plant and very little fruit.

What fertilizer should I use for tomatoes?

Use a balanced or slightly higher-nitrogen feed while the plant is still growing leaves, then switch to something with low nitrogen and higher phosphorus and potassium once the first flowers set. A 3-4-6 or similar ratio at flowering is the standard move. Feeding high nitrogen all season is the most common reason a healthy-looking tomato plant never fruits.

Do I need a soil test before buying fertilizer?

It is the cheapest way to avoid wasting money. A basic test kit costs less than a single bag of amendment and tells you your pH plus rough N-P-K levels. Most struggling gardens have a pH problem rather than a nutrient shortage, and adding more fertilizer to soil with the wrong pH does nothing because the plant cannot take the nutrients up.

Is it cheaper to grow from seed or buy nursery starts?

Seed is dramatically cheaper per plant — a packet costs about what one nursery start does and contains anywhere from 20 to several hundred seeds. The trade-off is time and equipment: you need to start 6 to 10 weeks before your last frost, and you need adequate light indoors. Nursery starts make sense for a handful of plants or for anything you are growing for the first time.

Do I really need a grow light to start seeds indoors?

For almost everyone, yes. A south-facing window delivers a small fraction of the light a seedling needs, which produces tall, pale, floppy transplants that never fully recover. An inexpensive LED or T5 bar a few inches above the tray fixes this completely and is the single biggest upgrade to indoor seed starting.

When should I start seeds for my area?

It depends entirely on your last frost date, which depends on your USDA hardiness zone. Tomatoes and peppers typically go in 6 to 8 weeks before last frost; squash and cucumbers only 2 to 3 weeks. The Furrow app works this out for your specific location and shows the sow window for every plant in the catalog.

How these picks get chosen

This list is the same product catalog that ships inside the Furrow app, where recommendations surface contextually — the Fertilizer Advisor suggests a specific N-P-K ratio for the plant and stage you are actually growing, and Seed Finder matches varieties to your hardiness zone.

Selection criteria, in order: whether the product does the horticultural job correctly, whether the formulation is honest about what is in it, and whether it is widely available. Commission rate is not a factor — Amazon pays roughly the same low single-digit percentage across the entire garden category, so there is nothing to game.

Prices are deliberately not listed. Amazon prices change constantly and a stale number on a static page is worse than no number — check the current price on Amazon before buying.