The three photographs above are the whole story of this clip: closed on a stem beside its support, opened out flat so the ring and the latch are visible, and set beside a coin so the size of the part is clear at a glance. This page is about the mouth of the clip - how it grips a stem, what it is gripped to, and how that grip is managed as the plant grows.

The job is written on this page in one line: to fix plants to canes, wire or branches gently. The word doing the work in that line is gently, because a stem is a living pipe carrying water to leaves above it, and anything that squeezes it closed at one point starves everything above that point. A clip that grips badly does not fall off; it does quiet damage that shows up later as a wilting head.

The shape is what prevents that. The stem sits inside the ring of the clip and the load is taken by the band around it rather than by a single face pressed against one side of the stem. When the two ends meet at the latch, the stem is held in the loop; it is not pinched between two jaws. That is the mechanical difference between a clip and a knot, and it is why the same part can hold a stem that will double in thickness without ever being tightened.

The body is moulded plastic and the clip is listed as weatherproof, so the grip does not change with the weather either. There is no cord in it to swell in a wet week, shrink in a dry one, or rot over a season.

The clip is made in one size. The specification gives it as 3.7 x 3 cm, and there is no second size in the range and no diameter table on this page. That is worth being plainly said rather than dressed up: the opening is sized around the crop the clip is named for, and the name on the page is tomato, with the same part listed for vegetables and for plants generally.

In practice that means the soft-stemmed crops of a greenhouse - tomatoes, cucumbers, peppers and cut flowers among them - where the stem is green, sappy and quick to thicken, and where a ring of this size closes around it comfortably for weeks. Close the mouth on a stem far thinner than the ring and the stem is not really held; try to close it on a woody branch far thicker than the ring and the latch will not meet.

If your crop sits outside that group, and especially if the stem is woody or unusually thick, send us the stem size at the enquiry stage. We will say plainly whether this clip is the right part for the crop rather than let a carton be ordered around a guess.

The page names three supports - canes, wire and branches - and one clip takes all three, because the ring can be closed around the stem and the support together when the two run side by side. That gives three different ways of using the same part in a house:

On a cane. The cane is set in the bed or in the pot, the stem is brought alongside it, and the clip is closed around both. As the plant climbs, a second clip is added higher up and the first one stays where it is, which is the method in the first photograph on this page. Canes are used again season after season, and so are the clips on them.

On wire and wire mesh. Where a house carries horizontal wire or a wire mesh panel, the stem is brought to the wire and clipped to it. The wire is a fixed line rather than a growing one, so the stem is clipped to it at the point where the two actually touch, and the clip is moved along as the stem's growing point rises past it.

On twine. Twine hanging from an overhead support wire is the lightest of the three, and the clip is closed around the stem and the twine together. Twine is slack by nature, so the clip is what gives it a fixed point; and because the clip opens, that point can be undone and remade a hand's width higher without the twine being cut or re-tied. Strings of twine and plastic hooks that carry them are part of the same greenhouse accessories group as the clips themselves.

Twine has one real advantage over a clip: the material is almost free. It has two costs of its own. The first is time - every tie is a knot made and, later, a knot undone, and a cropping house works through thousands of stems in a season. The second is that a knot cannot be adjusted without being undone: a tie that is right on the day it is made is too tight a month later, and loosening it means making it again.

A clip trades those two costs for a price per stem. What it buys is a closure that is opened and closed again on the same stem, at the same place or a new one, without being replaced and without anything being cut. Where a crop is long and the stems are handled repeatedly through the season, that trade favours the clip; where the crop is short, the stems are few and they are tied once, twine is still the lower-cost answer. The honest case for the clip is a house where stems are worked on again and again, not a house where they are tied once and left.

One thing a clip of a single size cannot do is grow. A stem that sits comfortably in the ring in March is a tighter fit by May, so the grip is managed by position rather than by size: the ring is opened, the clip comes off the stem, and it is closed again higher up where the growth is young and still slim, taking the support with it a hand's width further on. The clip that is too small for the stem it held in spring is the right size for the stem it holds in summer.

The same property is what makes the part last beyond one stem. Nothing in the clip ages against the weather the way cord does - the plastic is listed as weatherproof - so a clip released from a finished stem can be closed again rather than cut away and thrown out. The bag is opened, the clips are taken out and put to work, and the carton count behind them is on the carton sizes and shipping weights page.

Product	Plastic Plant Support Garden Tomato Clip
Material	plastic
Size	3.7 x 3 cm
Use	to fix plants to canes, wire or branches gently
Features	easy to use, weatherproof
Package	50 pcs per opp bag
Packing	120 sets per carton
G.W	7 KGS
N.W	6 KGS
Carton size	50 x 53 x 42 cm

We have made greenhouse and planting tools for above 35 years, and we supply over 1,200 different kinds of them. They are used by farms, and by agricultural science academies and institutes at home and abroad, and we have exported to more than 120 countries around the world.

The clips are quoted from our own works, so the price follows the moulding and the packing rather than a middleman's list. They are dispatched with the rest of the planting tools, on the same order and in the same shipment, and where a buyer wants to know how the works or the range is set up, our company page sets it out.

Extension material on protected cultivation and on crop support and training in the greenhouse is published by the NGMA, and reporting on commercial protected cropping appears in HortWeek.

Q: How does the clip hold a stem without damaging it?
A: The stem sits inside the ring and the band around it carries the load, so when the two ends meet at the latch the stem is held in the loop rather than pinched between two jaws. That is what the specification means when it says plants are fixed to canes, wire or branches gently.

Q: Which crops is this clip used on?
A: Tomatoes are the crop in the name, and the same part is listed for vegetables and for plants generally - in a greenhouse that means the soft-stemmed crops such as tomatoes, cucumbers, peppers and cut flowers, whose stems stay green and thicken quickly.

Q: Can the clip be fixed to twine, a cane or a wire?
A: Yes. Canes, wire and branches are the three supports named on this page, and the ring closes around the stem and the support together. On twine it is clipped to the stem and the twine as a pair; on a cane or a wire the stem is brought alongside and clipped at the point where the two touch.

Q: Should I use clips or tie the stems with twine?
A: Twine costs less per stem and suits a crop that is tied once. A clip costs more per stem and buys a closure that is opened and closed again on the same stem without being replaced, which is the better trade where stems are handled repeatedly through a long season.

Q: Does the clip have to be moved as the plant grows?
A: Yes. One size is made, so the grip is managed by position: the ring is opened, the clip is taken off and closed again higher up where the growth is young and still slim, carrying the support a hand's width further on.

Q: What is the clip made of, and how is a carton packed?
A: The material is plastic and the clip is listed as weatherproof. A bag holds 50 pcs and a carton holds 120 sets at 7 KGS gross and 6 KGS net, in a carton measuring 50 x 53 x 42 cm.

If you need to ask a question and get some help to find the best greenhouse for you, then just call us on +86 191 5068 3942 or send E-mail to sales@cngreenhouses.com